Table of contents

Efficient and sustainable infrastructure is an essential element for the growth of civilization and vital component for development of the society. Infrastructure helps distribute essential resources, facilitates productive mobility and consequently propels economic growth and empowers society to attain a better living standard.

However, ever-increasing infrastructure development inevitably affects the environment, which may result in catastrophic consequences for our planet. It is hence the duty of the engineers to minimize the environmental impact as well as to ensure the safety of the infrastructure even in case of extreme hazards. When designing and building new or maintaining the existing infrastructure one needs to balance the demands of high performance, economic growth and sustainable development in harmony with the environment.

With rise in global infrastructure, the importance of both natural as well as man-made hazards has increased over the past few decades. Several catastrophic events such as earthquakes, tsunamis, fires, hurricanes and explosions have clearly highlighted the need for developing new methods and technologies to reduce the impact of such disasters on structural performance.

In order to achieve this, various aspects of civil engineering from material to structural behaviour, from construction to operation, from geotechnical aspects to environmental considerations, from emergency preparedness to disaster management must be considered appropriately while taking into account the principles of sustainability.

To synergize the efforts of researchers and engineers worldwide, it is essential to promote the collaboration of experts across the globe. One such platform has been offered by the bi-annually organized conferences conducted by the Euro Asia Civil Engineering Forum (EACEF) since 2007. The primary goal of EACEF is to bring European and Asian civil engineers together to have an open exchange of ideas and commit towards advancement of research in civil engineering.

Given the new technologies and recent advancements in different aspects of civil engineering, the 7^th International Conference of the Euro Asia Civil Engineering Forum focuses on the two highly relevant topics of green engineering and safety of infrastructure against hazards. These proceedings showcase the results of the research efforts in many aspects and areas within broad spectrum of civil engineering. It provides a wealth of information for the researchers practicing civil engineering professionals.

Editors

Han Ay Lie

Harald Garrecht

Akanshu Sharma

Harianto Hardjasaputra

Acknowledgements

The editors wish to thank the scientific committee, review board and the editorial team for their efforts towards the success of the conference and these proceedings. Especially the untiring efforts of Florentina Pungky Pramesti, Senot Sangadji, Simone Stumpp, Monika Werner and Josipa Bosnjak are highly appreciated. The help provided by the students Felix and Onni in the proof checking and preparation of the final papers is greatly acknowledged.

List of Editorial Board and Scientific Committee are available in the pdf.

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Reconstruction after the Great East Japan Earthquake in March 2011 has been delayed. To suitably respond to similar large-scale disasters in the future, the implementation of a disaster management system at the local municipal level, aimed at rapid reconstruction that includes management of processes from pre-disaster to the reconstruction phase, is required. In this study, we develop a prototype of such a system, which is referred to as the Local Government Disaster Management System (LGDMS). For our study, we collaborate with a municipality in Kochi, Japan. In the LGDMS prototype, we use a Work Breakdown Structure (WBS) format, wherein the contents of each activity and roles of different organizations in those activities are defined based on a study of organizational problems and law and regulation issues among the central government, prefectural governments, and municipal governments. The Construction Management Committee of the Japan Society of Civil Engineers (JSCE) established a subcommittee for this research. This subcommittee is composed of university faculty members, local consulting engineers, and administrative officials in Tohoku and Kochi. The subcommittee is striving to implement LGDMS in several municipalities in Kochi.

Transportation system plays a vital role in sustaining the economic and social well-being of a community. Disaster or extreme hazard such as earthquake, storms, landslide, flood, terrorism, etc. has a major impact on the resilience of the road, especially in ensuring the impact toward the recovery for communities. Road infrastructure is linked to many encompassing factors such as road user, climate, economy, material, topography and periodic maintenance. Recently, unpredicted climate causes heavy rain, landslide, and flood resulting in high losses bared by the government on the repair and reconstruction works. Previous events have revealed that certain road areas in Malaysia are vulnerable after exposed to damage due to the natural disaster. This paper highlights the identified factors that contribute to adaptation on the escape route for road disaster resilient. A comprehensive review was done to identify a few missing approaches in the road network resiliency, which include a temporal route option as part of the adaptive routing solution. The research is expected to become a reference to overcome disruption in the road network in time of disaster or crisis while supporting the government initiative to strengthen the resilience of the nation's infrastructure.

The main objective of the environmental protection is the sustainable energy supply of residential areas. This is made possible by networking several buildings in the same district in order to produce a sustainable, efficient and self-sufficient supply of electrical and thermal energy. The second elementary topic is the conversion from combustion engines to electric mobility, i.e. from thermal to electrical energy. A novel concept of networking different storage facilities, energy producers and consumers will enable a sustainable, self-sufficient energy supply for districts. A special feature of this energy management design is networking of electrical and thermal systems with subsequent integration of electro-mobility into the districts plant system. Energy consumption and energy generation were simulated in an exemplary project of a district containing three new low-energy buildings. The results show that a self-sufficient supply of this district is possible with intelligent control of charging cycles and charging capacity and with the use of a new storage facility for electrical energy - a Compressed Air Energy Storage system. This model concept makes not only a considerable contribution to the electro-mobility conversion, but also enables an energy-efficient and sustainable electrical and thermal supply of the district.

Summer heat stresses the inhabitants of densely populated residential areas. It is one of the most serious environmental impacts. Heat can affect human health and lead to additional deaths even under current climatic conditions. Climate projections show a clear change signal for summer heat in the future. This means an increase in hot days and tropical nights, especially in urban quarters without networked green and fresh air corridors. This results in a high need for action with regard to summer heat protection and climate change adaptation measures. This paper makes a contribution to the 11th SDG "Sustainable Cities and Communities" with the target to improve the adaptation to climate change and resilience to disasters in terms of summer heat. It deals with the question of how adaptation measures can reduce the burden of summer heat on residents in their homes with the aim to decrease the disaster risk. The paper reviews current knowledge about common adaptation measures, summarizes first results of thermal simulation calculations for the evaluation of effectiveness of adaptation measures, including the effects of residents' behaviour, and makes recommendations for preventive action. The results show that the development of sets of adaptation measures for summer heat waves must not be regarded separate neither from adaptation for cold winter seasons nor from climate protection regarding energy efficiency. Further, it shows the importance of including the aspect of acceptance by the residents in the planning process to make climate change adaptation of their buildings successful.

To predict the corrosion of reinforcing steel, the electrochemical properties of reinforcing steel with different concrete mix proportions and chloride content were studied. The water to binder ratio of concrete was varied (0.45 and 0.60). Coal fly ash was used to replace OPC (0 and 30% by weight of the total binder). The initial chloride was 0, 2, and 4% by weight of concrete. Potentiodynamic polarization testing was conducted by controlling the moisture of specimens. The Tafel slope, corrosion potential, and corrosion rate were analyzed from the testing results. Results show that chloride content significantly affects the electrochemical properties of reinforcing steel. The anodic Tafel slope decreased as chloride content increased. The cathodic Tafel slope increased when the water to binder ratio decreased, or when the fly ash content increased due to a denser concrete pore structure, limiting oxygen diffusion. Results from this study can be used to simulate the corrosion of reinforcing steel and predict the service life of reinforced concrete structures. Also, the electrochemical compatibility between existing and repaired sections can be evaluated to ensure the durability of repaired RC structures.

The amount of cement paste used in concrete depends on aggregate particle packing, where the denser combination among particles with different particle sizes results in a minimum volume of voids (Vv). Theoretically, cement paste volume (Vp) is required to fill the void with the combination of fine and coarse aggregate, i.e., Vp/Vv = 100%. The purpose of this paper was to propose a concrete mix design method that could maximize the particle packing of aggregates to reduce the cement content in concrete mixture, hence producing low-cement concrete (LCC). The variables proposed were the ratio between the volume of paste to the volume of voids (Vp/Vv) as opposed to the cement content and the use of superplasticizer to control the workability of the fresh concrete. The results showed that by the combination of multi-sized coarse aggregates and fine aggregate, the smallest void volume of 23.5% could be achieved. The theoretically lowest cement content needed for a mixture with w/c 0.5 was 287 kg/m³. However, after trial mixing, the cement requirement was found to be almost equal with conventional concrete, i.e., about 310 kg/m³. Workability of the mixture depended on the paste volume to void volume ratio (Vp/Vv > 100%) and was greatly influenced by the superplasticizer content. The use of excessive superplasticizer could cause bleeding due to lack of fine particles in the low cement concrete mixture. The use of cementitious material, such as fly ash by 50%, to replace cement, significantly improves the workability and reduces the cement content below the minimum cement requirement with similar compressive strength as the water to cementitious ratio mainly controls compressive strength.

Low-cement concrete (LCC) is made by considering the particle packing of the constituent material. The minimal content of cement paste is achieved by optimizing the coarse and fine aggregate particle size gradation to reduce the void volume (Vv) between the aggregate particles. Theoretically, the minimum cement paste can be calculated as the cementitious paste volume (Vp) filling the entire void volume (Vp/Vv = 100%). Practically, low fine or powder material content would reduce concrete mixture cohesion and cause bleeding and segregation. Viscosity-modifying admixture (VMA) can be added as an alternative to adding more cement powder or supplementary cementitious materials to improve the cohesion and stability of the LCC matrix. This study investigated the role of VMA addition in increasing stability in low water to cement ratio (w/c) mortar with an excessive dosage of superplasticizer and in high w/c mortar designed with low cement content. The results showed that adding VMA reduced bleeding and increased cohesion in the fresh mixture, and also increased the compressive strength of the hardened mortar. Although the addition of VMA cannot increase the workability of LCC, it had a beneficial effect when added to an LCC mixture as the 28-day compressive strength of the concrete with w/c of 0.5 was increased from 18.68 MPa to 22.93 MPa by adding 0.4% VMA by mass of cement.

Modern concretes are characterised not only by rising demands on properties but also by increasingly complex compositions. With sophisticated formworks and dense reinforcements, the trend in concrete technology continues towards to self-compacting and easily-compacting concretes. The use of highly effective superplasticizers makes these concretes not only more efficient but also more susceptible to environmental factors and influences. Compliance with desirable fresh and hardened concrete properties is becoming increasingly problematic. In this case, there are no methods for testing today's concretes, especially the easily-compacting and self-compacting concretes, which are suitable for construction sites. Because of their sensitivity, however, these should be examined separately for their tendency to segregation and, in this context, for their sedimentation stability. For this reason, a test method is currently being developed at the Institute of Construction Materials at the University of Stuttgart, which is intended to examine concretes in particular for this problem. First preliminary test in a simplified procedure have already confirmed the basic idea of testing.

The world is facing the challenges of climate changes due to the increase in CO₂ emissions. Cement production is one of the biggest contributors to CO₂ emissions due to combustion processes that require high temperatures. The new development in building construction showed that fly ash based Geopolymer concrete can be as structure materials to reduce or even eliminate ordinary Portland cement concrete. This paper presented the research results of fly ash based geopolymer concrete mechanical properties, like the compressive strength, flexural strength, and Elastic Modulus. The data were collected from the test results of geopolymer concrete specimens made from 2 sources of Fly Ash with varying concentration of sodium hydroxide solution from 4 M up to 12 M. The range of achieved compressive strength was from normal to high strength concrete. The correlation between the compressive strength and flexural strength and the Elastic Modulus of geopolymer concrete will be the highlight of this paper. The mathematical formulation of compressive strength and its flexural strength and Elastic modulus will be determined and compared with normal Portland Cement Concrete.

Improperly constructed cold joints lead to poor water tightness. Water, chloride ions, and other harmful substances can therefore enter through the joint, causing the accelerated corrosion of steel bars. In this study, the surface wave group velocity profile, which can identify velocity at variant depths beneath concrete surfaces, was used to determine the interfacial condition of a cold joint. The proposed test method performed a single test with one impacting source and one receiver placed on a concrete surface across the joint. The short-time Fourier transform (STFT) and the reassignment technique were used to process the received signal and obtain the image of the group velocity spectrogram. The surface wave group velocity profile was then extracted from the spectrogram. A 0.4 m-thick reinforced concrete wall containing a cold joint was constructed for the experimental studies. The experimental results revealed a sudden decrease in wave speed for wavelengths larger than 0.2 m: the Rayleigh wave speed dropped from 2,000 m/s for normal concrete to 1,300 m/s for concrete including a cold joint. These results suggest that the rebars near both sides of the wall surface constrained the joint from separating up to the depth of 0.1 m; however, a poor interfacial condition was found near the center of the wall.

Aggressive environmental conditions, such as exposure to the sea climate or use of de-icing salts, have considerable influence on durability of reinforced concrete structures due to the reinforcement corrosion induced damage. In the present paper, the recently developed coupled 3D chemo-hygro-thermo-mechanical (CHTM) model for concrete is discussed. The model takes into account the interaction between non-mechanical processes and mechanical properties of concrete (damage). The mechanical part of the model is based on the microplane model. It is validated through a 3D transient FE analysis of a pull-out of corroded steel reinforcement from a concrete beam-end specimen, which was exposed to aggressive environmental conditions. For the corrosion phase, the influence of the anode and cathode position on the electric potential, current density, corrosion rate and corrosion induced damage is investigated. Moreover, the effect of corrosion on the pull-out capacity of reinforcement and the influence of transport of corrosion products through cracks are studied.

In the present paper, the influence of thermally induced damage of reinforced concrete (RC) slabs on their impact properties are numerically investigated. The RC slabs are first pre-damaged through fire load and then loaded by the impact of hammer. Transient 3D finite element (FE) thermo-mechanical analysis is performed. Subsequently, impact simulation is conducted based on the explicit multi-body dynamic analysis and contact algorithm with adaptive element deletion technique. As a constitutive law for concrete rate and temperature, dependent microplane model is employed. The co-rotational Cauchy stress tensor and Green-Lagrange strain tensor are used in the framework of total Lagrange FE formulation. The numerical results are discussed and compared with those obtained experimentally. It is shown that pre-damage of RC slab through fire reduces the impact resistance of the slabs, and that the simulation is able to realistically replicate the experimental tests.

Creep of concrete can be partly attributed to the time-dependent deformation of cement paste and partly to the interaction between load-induced damage of mortar (hardened cement paste) and its non-elastic deformations [1]. The heterogeneity of concrete and related interaction between load-induced damage and non-elastic deformation of mortar can have significant influence on the long-term response of concrete. Some aspects of the problem have been investigated in [1] through 3D finite element (FE) analysis of a concrete cylinder at meso-scale. The concrete is treated as a bi-phase composite material, consisting of coarse aggregate and mortar matrix. The constitutive law for mortar is based on the microplane theory, while the aggregate is assumed to be linear elastic. The results obtained for basic creep and shrinkage, at different levels of applied uniaxial compressive load (both separate and combined action) are reported in [1]. This paper mainly focuses on the effect of cyclic variation of environmental temperature and its interaction with the load-induced damage, basic creep and shrinkage of mortar. It is shown that with higher loading level the increase of time deformation of concrete becomes progressive and the variation of environmental temperature strongly influences time-dependent concrete response.

Concrete containing cement, sand, gravel, nickel slag, water and superplasticizer were processed using normal intensive mixing. The strength of concrete is determined by the interfacial zone between binder paste and aggregates. Due to the weathering of natural aggregates with time, a morphology with rounded edges is obtained, reducing the interlocking with the paste. Hence, it is interesting to investigate the use of nickel slag as a sand replacement in concrete since this material has sharp angular edges, which can improve the cohesion of the concrete. This research investigates the use of nickel slag as the replacement of sand in concrete. Various concrete samples were produced with the increasing nickel slag content from 0% to 50% every 10%. A water-cement-ratio of 0.35 was chosen in this study. Concrete mixes were assessed for their compressive strength and workability. The obtained results showed that the strength of the concrete increases together with the increasing nickel slag content in the concrete mixture. Also, the results demonstrated that the slump increases with rising nickel content. In addition, there was no bleeding in fresh concrete mixture in this research.

The distinctive characteristic of lightweight concrete lies in its combination of load-bearing and insulating properties. In order to produce this material using modern manufacturing processes such as spraying or printing, certain hurdles must be overcome. For example, a multi-component concrete has to be developed that is not only optimized concerning its rheological properties, but also takes into account the influence of the pumping process on its characteristics. Especially concerning the objective of a heat-insulating concrete, the pumping process has a decisive influence on the range of properties. For pumping applications, the system technology limits the largest grain size of the concrete mixture. This leads to very fine concretes or mortars, which react sensitively to the applied pressure. The occurring pressure-induced compaction leads to an increase in strength due to an increment in bulk density and the damage of lightweight aggregates. This, in turn, affects the thermal conductivity of the material. Based on a lightweight concrete developed at the Institute of Construction Materials at the University of Stuttgart, these challenges are highlighted and discussed in the following paper. The concrete was utilized for pumping and spraying experiments at a testing facility in collaboration with the Institute for System Dynamics, and the resulting thermal properties were examined at the Material Testing Institute, University of Stuttgart. Furthermore, the interaction between the employed system technology and the properties of the pumped lightweight concrete, such as consistency, strength, bulk density, and thermal conductivity was examined and analyzed. Results showed that the concrete properties reacted sensitively to different configuration setups of the pumping system and the conveyance line. Hence, a clear interdependency between the mix design and the employed machinery could be observed and has to be considered in future endeavours.

The influence of calcium chloride (CaCl₂) as an accelerator for the compressive strength development of concrete made with type I Portland pozzolan cement (PPC) as a hydraulic binder has been investigated. Natural sand and crushed stone were used as fine aggregate and coarse aggregate, respectively. The mix proportion of concrete, by weight, was 1.0 binder: 2.1 fine aggregate: 3.4 coarse aggregate and the water-binder ratio was 0.57. The calcium chloride added to the concrete mixture was 0%, 1.0%, 1.5%, and 2.0% by binder weight. The compressive strength test was performed at 1, 3, 7, 28, and 90 days. The test results show that adding CaCl₂ to a concrete mixture accelerates the development of compressive strength. The compressive strength gain was about 36–48% at 1 day and about 29–33% at 3 days, compared to control concrete. Moreover, it increases the compressive strength of PPC concrete about 3–16% at 28 days and about 7–19% at 90 days. The optimum dose of CaCl₂ to accelerate the development of compressive strength at the early age and to produce the highest compressive strength in the long-term was about 1.5%.

Designing concrete meeting the principles of sustainability becomes urgent in the construction of buildings and other civil engineering infrastructures. Sustainability of concrete can be assessed by considering its environmental, economic and social impact. Each impact may cover multi-criteria and parameters for the assessment. In this respect, the designers require practical tools so as to select the best alternative concrete mix design fulfilling the multi-criteria. This paper proposed an eco-durability index (EDI) as such tool for assessing the balance performance in term of environmental impacts and durability of self-compacting concrete (SCC) incorporating high volume fly ash. The fly ash content is in the range of 50%-70% of replacement level i.e. a fraction of cement replaced by weight of fly ash. The parameters adopted for assessing the environmental impacts (ecological index) are embodied primary natural resources depletion, embodied energy and embodied CO₂; while the time to corrosion initiation period due to chloride ion ingress by diffusion mechanism is taken as durability parameter. The chloride ion diffusions of the concretes under study were determined following ASTM C1556 from the chloride profiles. The chloride profiles were obtained by salt ponding test according to AASHTO T259. The amount of chloride ion with respect to the depth of its penetration was determined by XRF method. Within the scope of this study, it is shown that an increase of fly ash will reduce the environmental impacts of SCC. However, the durability of concrete does not show a similar trend. Therefore, a balance performance considering the environmental impacts and durability is searched for by using the value of EDI. Based on the EDI, it is indicated that SCC with 70% fly ash replacement level gives the best alternative of SCC with respect to balance performance of environmental impacts and durability.

This contribution presents a set of experimental results on fiber-reinforced innovative lightweight panels (FRIL-panels) having thickness of 12mm. These panels are prepared with a peculiar foamed concrete that has a high viscosity and cohesion in the fresh state, which makes it particularly suitable for 3D printing applications. The FRIL-panels can be used for internal partitions, external infills, and suspended ceilings of buildings as more effective solutions than conventional plasterboard ones, with better thermal insulation and acoustic absorption properties due to the internal air-void microstructure. The aim of this work is to investigate the out-of-plane resistance of FRIL-panels, prepared with a density of 800kg/m³, under displacement-controlled three-point bending tests. In view of potential use in the precast industry, the FRIL-panels were placed into an accelerated concrete curing tank so as to speed up the overall production process. Modulus of rupture, ultimate deflection and collapse mode of FRIL-panels are critically analysed and discussed.

Performance of concrete is dependent on a number of factors. It is difficult to understand the influence and interrelationship among these variables, when there are many. Dimensionality reduction techniques can yield the best possible data interpretation based on the variance in data, without loss of much of original information. This paper presents the application of dimensionality reduction technique for analysis of data and decision making in the field of Concrete Technology.

UHPC and UHPFRC are remarkable materials which have properties with significant advantages. In addition to high compressive strength, they have higher tensile strength than conventional concrete. To study the tensile strength of UHPC and UHPFRC, a series of experimental programs have been developed at Kassel University. The effects on the fibre efficiency produced by varying the volume of the steel fibre percentage are discussed. When the results are compared to proposed equations generated in some European countries, the results are generally similar and confirmed satisfactorily. Satisfying justifications are also obtained when applied to the results for the axial tensile strength of the UHPFRC specimens. By using the proposed equations, the fibre's effective (efficiency) stresses in UHPFRC in the stages of fibre activation and pullout can be calculated. However, not all the results of this study can be confirmed by other countries (e.g. USA, Japan). Diverse circumstances taking place during the production of the material may have to be taken into account to explain the dissimilar output. Studies of the tensile strength of UHPC and UHPFRC are important, with the aim of supporting more documentation for the development of recommendations, guidelines, standards and norms; thus meeting the needs of structural design.

This study evaluates the feasibility of using fly ash cement mortar as the substitute of commercial anchorage adhesives by means of experimental tests. Temperature effect is also investigated. Different amounts of fly ash are added in the cement mortar and the mortars are mixed according to the proportion design methods illustrated in the literature. In addition, silica sand is used instead of river sand in some mortar. By summarizing the results of flow test, compression test, and fire resistance test of the mortar specimens, three better mixture proportions are determined. The pull-out specimens were prepared by implanting #3 (D10) steel bars into concrete cylinders to a depth of 9 cm. The specimens for temperature effect tests are heated and kept in furnace under 400°C or 600°C for 60 minutes and cooled naturally before conducting experimental tests. The feasibility assessment is carried out by comparing the pull-out test results of this study with those of rebars installed with commercial adhesives from earlier study. The results have shown that rebars installed with the proposed cement mortar may achieve acceptable bonding effect, although the bonding strength at room temperature is lower than those of commercial adhesives-installed rebars.

A self-healing phenomenon, in which the cracks become partially refilled as a result of rehydration of cement particles and deposition of CaCO₃, has been observed in narrow cracks under a constant supply of moisture. Also, according to previous studies, the self-healing performance can be maximized by changing the temperature and pH to control the crystal form of CaCO₃. In this study, attention was paid to the crystal form of CaCO₃ generated in the self-healing process of a cement-based composite material and, in order to generate denser crystal of CaCO₃, the change in the crystal form of CaCO₃ generated in the hardened cement paste by changing the temperature condition was observed and analyzed. Also, to increase generation of CaCO₃ which is a self-healing precipitate, nano-sized ultrafine CO3^2- bubbles using CO₂ gas were used along with effective supply of Ca²⁺ through adjustment of aqueous solution. As a result, the possibility for effective generation and control of denser vaterite together with calcite was confirmed by adjusting the temperature to about 40°C under the condition of pH 12.

The objective of this study is to investigate the optimum nano-natural pozzolan (NNP) content in the NNP-based binder concrete. NNP was obtained by grinding a local volcanic scoria for six hours. Twenty-four concrete mixes with four w/b ratios (0.4, 0.5, 0.6 and 0.7) and six-replacement levels of NNP (0%, 1%, 2%, 3%, 4%, and 5%) have been produced. The investigated concrete properties were the compressive strength, the water penetration depth, the concrete porosity and the chloride ion permeability. The efficiency factor (k) of NNP in terms of compressive strength was calculated using the Bolomey equation. Durability indicators have been used to globally evaluate the behavior of NNP-based binder concrete versus control concrete. The results revealed that the efficiency factor (k) decreased to some extent when the NNP content was more than 4%. The calculated durability indicators showed that NNP contents of 3-4% had approximately the highest indicators values. These indicators would be helpful for concrete mix designers. Some correlations between the investigated properties were derived from the analyzed data. The modification of the microstructure of NNP-based cement paste has been observed, as well.

Unmanned Aerial Systems (UAS) are a growing aircraft technology being used in all sorts of industries. Despite studies exploring the potential applications of UAS, such as photographs or video collected by UAS, its benefits for the supervisory job on construction sites is not well understood. This paper presents a comparison of the supervisory cost generated using UAS and that from the conventional method. In this study, both five projects applying UASs and another five using the conventional supervisory method participated voluntarily. The survey used questionnaires targeted to people working in a supervisory job within the five projects. The results showed that most potential applications were particularly suited for tracking and monitoring job progress, evaluating safety monitoring and support, and inspecting difficult areas. In comparison, it was found that applying UAS was more cost-effective than the conventional supervisory method. The average supervisory cost to total wage generated from the project supervisory job by applying UAS and conventional methods were 0.212% and 0.450% respectively. Despite insignificant differences, the study provided a picture that, by applying UAS properly, it would be able to have a potential cost saving in the supervisory job in construction.

A case study of the road subsidence hazard that occurred during the construction of a cable tunnel was conducted. The cable tunnel was built 30 m below the ground surface by using the shield tunnelling method, parallel to a sewage pipe with a diameter of 2000 mm. During shield docking, the bolt of the seal plate in the shield segment ruptured. This rupture led to water flooding into tunnel and the settlement of the ground surface. The causes of the subsidence hazard were analysed and discussed. The results of this case study indicate that risk assessment and hazard analysis of shield tunnels should be conducted separately in the planning, design, and construction phases for ensuring disaster mitigation. To avoid the occurrence of a subsidence hazard, sensors should be embedded 30 m below the ground surface and near the shield machine. Using monitoring sensors and increasing the number of observed frequency are effective in enhancing the settlement sensitivity so as to provide early warning information. Ground improvement is suggested even while using the concentric interlace docking method.

Procurement of construction projects in Nigerian Federal Universities has been affected by unethical procurement practices amongst the stakeholders and projects parties concern. This study aims at developing a framework to mediating the large negative effects of unethical procurement practices on construction projects development. Conflict of interest factors, especially at the tender and bid evaluation stages, were identified as the major unethical practices affecting construction procurement processes of infrastructure projects negatively. Data were collected using a survey questionnaire distributed to construction procurement stakeholders of nine randomly selected Nigerian Federal Universities. Mediation effect of ethical procurement practices was tested between the conflict of interest factors and procurement of construction and infrastructural projects. The findings revealed that conflict of interest factors were found to have large negative effects on procurement of construction and infrastructural project, and ethical procurement practices identified and introduced as mediating variables were tested and verified to possibly mitigate the effects of conflict of interest factors affecting the procurement of construction and infrastructural projects in Nigerian federal universities. Hence, the study recommends that procurement entities concern should ensure compliance with Public Procurement Guidelines (PPGs), which highlights ethical requirements for tendering, bid evaluation and construction processes for the procurement of construction and infrastructural projects.

Procurement management has been a focal point of many studies. This led to several industry stakeholders to produce reports on how best to achieve it. The construction sector comprises of loosely integrated activities and assemblage of various products from other industries. These characteristics make it unique from other industries, and as such, its success is largely dependent on the quantum of knowledge applied in its products design, strategy and implementation. However, clients of the industry and other stakeholders failed to appreciate this salient difference between the construction industry and others, thereby treating the procurement of its product as though is off-the-shelf. This is found in several procurement frameworks reviewed by this study, when the procurement for construction is lumped together with the same consideration as procurement for goods and services. Given the above perspective, this study explores the literature in order to develop a knowledge requirement theoretical framework for construction procurement management. An exploratory design was used as a stand-alone approach through a critical review of the extant literature on construction complexities, general procurement competencies and management. The reviews were applied in the context of systems thinking theory to develop a knowledge requirement theoretical framework for construction procurement management. The framework conceptualized knowledge requirement for construction procurement management as a conglomerate of knowledge (system) that is made up of units of knowledge aligned to accomplish a construction project. Thus, for full attainment of construction procurement management knowledge, a manager needs to possess the various units of knowledge that are appropriate for the execution and coordination of the various activities in construction procurement processes.

This study investigates how semiotics can be applied to enhance construction operatives' health and safety (H&S) signs comprehension in Yola metropolis, Nigeria, with a view to improving on H&S management that will curtail the occurrence of accidents. Adopted ISO (9186-1) questionnaire for testing H&S signs comprehension were administered to 60 construction professionals and operatives that are executing 5 government building projects. Responses were subjected to descriptive and inferential statistics respectively. Findings revealed that 11 of the 15 H&S signs studied ranked highly relevant for curbing accidents on construction sites while the remaining ranked relevant. For factors influencing H&S signs; training ranked highly influential, experience ranked influential, education ranked moderately influential. While culture, age and gender were ranked least influential respectively. The study recommends: contractors H&S safety compliance records be considered as one of the bases for contract award, safety consciousness be integrated in the overall procurement process, H&S requirements compliance certificate should be introduced and issue to compliant contracting firms, erring contractors on non-adherence to H&S provisions on construction sites be sanction, and construction operatives should be continuously train on H&S signs comprehension.

Industrial revolution is a series of events driven by the growth of technological innovations, and so far, the world had witnessed the first three industrial revolutions. Today, a new revolution referred to as the fourth industrial revolution is entering even though it is still in its early stages of development. Many developed countries had established their own roadmap or strategic plan as a first step. However, only a few of them touched the construction sector even though the construction industry provides a significant contribution to the country's GDP. Based on this understanding, there is a fundamental need to give a clear view of Industry 3.0 to Industry 4.0 from the construction industry's perspective, since most users are still finding their way in this transition. An extensive literature review is used to define the scope and terms of the field of construction in the industrial revolution. Towards this goal, a clear definition and concept of each revolution, key technologies related to construction and challenges faced by the industry will be explored. Simultaneously, this review paper also benchmarked a few documents as a simple guide in the transition process to the fourth industrial revolution to avoid a lag in a world where changes are swift and sudden. Therefore, this review paper contributes by providing a better understanding of the challenges and trends in Construction 4.0 to academics and practitioners. Moreover, it will spark new ideas on the policy or strategic roadmap development in the future.

Civil engineer plays an important role in construction industry because they have been entrusted to create sustainable world and to enhance the quality of life. In order to play their role successfully, civil engineer needs to possess many and varied knowledge and skills, as well as supported by embracing attitudes. This study is aimed to explore the importance and achievement of attributes of civil engineers based on profile of the 2025 civil engineer that has been launched by American Society of Civil Engineering (ASCE). The attributes consist of 21 points those are organized into the categories of knowledge, skills, and attitudes. The research was conducted by asking respondents to fill out a questionnaire to assess the importance and performance of each attribute. The data has been collected from 100 practitioners who work in various construction companies in Indonesia. Descriptive Statistic, Importance Performance Analysis (IPA) and correlation analysis have been implemented to analyze the data. The study found communication is considered as the most important attribute and in a highest performance. Thoroughly the Spearman Rank Correlation analysis shows the level of importance and performance have a strong and positive correlation. However, the importance and performance level of knowledge about sustainability only in the rank of 16 and 18. This result shows that in Indonesia knowledge about sustainability has not been considered important.

Devastating accidents in construction projects have elevated interests on providing early attention to safety hazards in design phase. Calls for changes in safety practice, through the Prevention through Design (PtD) concept has become increasingly vocal in various countries. In Malaysia, a Guidelines of Occupational Safety And Health in Construction Industry (Management) (OSHCI(M)), which stems from the PtD concept was launched to provide guidance for designers to enhance their PtD capability. This paper aims to explore the current PtD knowledge among C&S designers, in order to gauge the initial understanding towards OSHCI(M) implementation. Data were collected from 70 C&S designers in Malaysia through questionnaire survey and discussion conducted from four series of PtD workshops. The findings revealed that despite the current state of C&S designer's knowledge still needs to be improved, majority of them have been very positive and supportive on the OSHCI(M) implementation. A number of recommendations towards improving the PtD knowledge have been highlighted; PtD early education; the use of pedagogical approach in PtD teaching; continuous training and establish integrated PtD educational resources. This study extends the PtD literature in construction context, in particular into the advancements towards improving the PtD knowledge among designers in the developing countries.

Despite its considerable contribution to the economy of a country, construction industry is held responsible for degrading sustainability in general, and environment in particular, in many ways. For example, it consumes about 40% of global resources and, generates almost half of all the pollution. However, their nature and degree may vary according to the type and scale of the projects, and often can be area or country specific. Especially, no research seems to have been conducted previously in Brunei Darussalam for identifying pollution from construction. Therefore, this study was undertaken to identify sources of construction related pollution and their mitigating strategies. However, this paper focuses only on sources of pollution and summarizes the outcomes from a questionnaire survey of 107 responses, comprising clients, contractors and consultants. Five groups of pollution were identified, with various sources within each group: air pollution that includes dust and GHG (greenhouse gas), water pollution, noise pollution, and solid waste. All the sources were observed to have different degrees of criticality, i.e. either critical or more critical, implying a general critically of the identified sources of pollution. However, the focus seems to be on developing an industry wide awareness towards pollution, with contractors to play key role to pollution and relevant activities, probably due to their engagement in executing construction at sites. The next step of the study is to further investigate for a holistic solution, while the outcomes are expected to help policymakers to develop and/or take appropriate measures to control pollution.

'Greening existing buildings' is an approach to apply the principles of green building to old and existing buildings with environment responsive and energy efficient 'green features' or devices, e.g. through retrofitting, as and when required. It allows considerable reduction of energy consumption and greenhouse gas emission. However, the practice is not getting momentum, especially in Brunei. A study was therefore undertaken to generate and/or gauge the awareness of 'greening existing buildings', through identifying and assessing the key benefits of greening existing buildings. This paper presents the outcomes of 68 responses from an ongoing questionnaire survey of mainly clients and consultants. 15 benefits were identified, with "reduced energy/electricity consumption" topping the list, and "increase in building occupancy/usage rates" at the bottom. All the 15 benefits were found to be significantly important, both in the total sample, as well as in the groups of clients and consultants, and people with or without experience of green building. The two-way grouping also revealed that the above paired groups significantly showed their importance of different benefits in the same way. The outcomes are therefore considered as a general consensus of the respondents on the benefits of greening, despite some disagreements on the relative rankings of individual benefit by different groups of respondents. The outcomes are largely similar to elsewhere, and show a general awareness of the respondents to the overall benefits of greening existing buildings. Such outcomes are expected to inspire the clients to undertake more greening projects to demonstrate proven benefits. This is expected to help wider use of greening existing buildings in Brunei and elsewhere and thereby implement sustainable development.

The limitations of Discounted Cash Flow (DCF) method for capturing the opportunity value phenomenon in the uncertainty of housing investment analysis cause difficulties in the decision-making process for the investors. Flexibility factor becomes the obstacle for investors in project uncertainty. Real Options Analysis (ROA) is an important factor included in the DCF method because it offers managerial flexibility in the uncertainty of housing investment decision making. Flexibility in ROA is a right and investors do not have an obligation to respond to uncertainty in project investment. In this research, the type of flexibility on ROA used is an option to carry out promotional activities. The research results indicate that promotional activities affect the increase in Net Present Value (NPV) so that the benefits are maximized. Comparison of the results of investment analysis between ROA and DCF methods indicates an added value due to the existence of such flexibility. The investment simulation of ROA method was conducted using Monte Carlo method approach. The role of flexibility from the simulation is obtained by increasing the added value by 5.2%, and optimal promotion occurs in the first two years of investment.

The erosion under a spillway can be a long-term issue that threatens the structural integrity of a water reservoir. The heavy rainfall associated with storms or typhoons could cause a serious flood if the spillways do not function properly. The spillway under investigation was suspected to be defective after they had been commissioned in 1987. Potholes and subsurface cavities were confirmed in the safety assessment using various NDT techniques including ground penetrating radar and impact echo. The engineering team applied the repair project that aimed to remedy the deteriorating concrete structure. The GPR inspection was able to differentiate the repaired region from the cavities under concrete slabs. The results were verified against other measurement data obtained independently. Hence, the GPR technique is effective for quality check of grouting repair of spillways. Repetitive GPR scans were also carried out after the rehabilitation of spillways. Not only the quality of repair can be evaluated, but the scans were also provided as the baseline record for long-term condition assessment of the spillway-reservoir system in the future.

Conventional contracts are one of the road maintenance contracts based on the number of jobs measured and paid at an agreed level for different work items or referred to as unit price contracts. Meanwhile, performance-based road maintenance determines the minimum conditions of roads, bridges, and traffic assets that must be fulfilled by contractors. National road maintenance in several developed countries has successfully used integrated contracts, performance-based contracts. This is followed by the developing countries that previously had problems with the quality of national roads in which they were unable to provide the desired level of service. This performance contract prioritizes products and it is up to the contractor how to achieve this. Therefore, the choice of design, application of technology, innovation, process, and management are all determined by the contractors. This allocates higher risks to contractors compared to traditional contracts. But at the same time, it opens opportunities to increase margins where increasing the efficiency and effectiveness of design, process, technology, and management can reduce costs to achieve established standard performance. This study uses simulations to obtain the duration of fair and optimal contracts for the government and contractor. Duration 5-7 years is determined a duration that can provide benefits for both parties.

Structures, such as quay walls, have to meet a particular level of safety. Consequently, in the Eurocode standards, three reliability classes are distinguished, each corresponding to a target reliability index and set of partial factors. In this study, more insight is acquired into the relationship between the quay wall's construction costs and the associated reliability index β. It appeared that the marginal costs of safety investments of quay walls are fairly low and in the same order of magnitude of the uncertainty of the estimate of the construction costs. Hence, it seems that the current reliability classes, as defined in the Eurocode standards, are non-efficient for quay walls. In addition, this study investigates the influence of the partial factors and three failure mechanisms on the construction costs and the reliability index. It was concluded that for the considered cases, the soil's angle of internal friction strongly influences the construction costs and the β of the quay wall. Furthermore, it follows that economic optimisation in the probabilistic design of quay walls is possible by increasing the target reliability index of the failure mechanism 'insufficient passive soil resistance' and decrease the target reliability index of 'yielding of sheet pile profile'.

Toll road infrastructure investment will affect the production sector, where the role of transportation is to be the logistics function of the manufacturing industry. The government policy based on the acceleration of toll road investment is expected to boost production performance. The local government is expected to provide support by increasing the economic potential of the region along with the policy. This research tends to describe the contribution of the toll road infrastructure investment in the Manufacturing Industry Sector in West Java Province. The empirical data result shows the difference of the significant efficiency level of the Manufacturing Industry Sector from connected district areas/cities compared to the areas that are not connected to the toll road (+ 6%). With the T-test Pair analysis, there is a significant difference against the value of efficiency level for the areas that are connected to the toll road from the Manufacturing Industry Sector once the Cipularang Toll Road begins to operate (+ 4%).

In this paper, a foundation inspection strategy was developed to determine the condition on a fully-submerged pile bent foundation supporting an overwater vehicular bridge in Taiwan. The electrical resistivity tomography inspection displayed the overall conditions of the salt-content canal. Using the reciprocal principle-based ultra-seismic inspection could finely determine the foundation depth. The time lapse analysis and traditional frequency analysis provided varying degrees of reliability on the pile length estimate, positively re-confirmed with the design charts. The entire investigation demonstrates the conclusiveness in determining the foundation depths when two testing methods are corroborated with appropriate analysis modes.

The western foothills geological zone of Taiwan contains sedimentary rocks such as conglomerate, sandstone, shale, and mudstone. These formations often cause severe damage to life and property during a natural disaster such as earthquake and rainstorm, especially on a dip slope. This paper presents the results of long-term ground monitoring on a high sliding potential dip slope located in the western foothills of central Taiwan. The slope has been went through substantial movements induced by rainstorms during the monsoon season or after a typhoon. By comparing the rainfall data and long-term in-situ measurement of ground displacement using total station and inclinometer, we find that the movement of this slope is highly related to regional rainfall. The slide mechanism can be attributed to the infiltration of rainfall that tends to increase the driving force of the upper sliding mass and decrease shear resistance on the interface between sandstone and shale.

Fly ash is categorized as pollutant produced from coal combustion, where the waste produced is around 4% of the total coal usage. This will be extremely dangerous since this waste is produced continuously. Mount Sinabung, which is located in North Sumatera, Indonesia, has erupted since 2010 and released a lot of ash pollution. Sinabung and fly ash can cause environmental and health problems for the people who live near the area. In the other hand, limestone is one of the building materials that can be used for soil improvement. When limestone with clay minerals reacts, it forms a strong and hard gel namely calcium silicate which can coat and bind clay particles and close the pore pores, so that it can reduce the soil plasticity index. This research analyzes the optimum CBR value and the optimum mixture. Variation of the mixture used was 2% and 4% limestone with the addition of 2%, 4%, 6%, 8%, 10%, 12% and 14% fly ash and 2% and 4% limestone with the addition of 2%, 4%, 6 %, 8%, 10%, 12% and 14% of Sinabung ash. The result shows that the mixture of limestone and Sinabung ash indicates the bigger value of CBR compared to the limestone and fly ash mixture. Furthermore, the largest CBR value was found in the mixture of 2% limestone and 8% Sinabung ash with 9.01%.

Enzymatically induced calcite precipitation (EICP) is a new breakthrough for liquefaction prevention. This approach uses urease enzyme directly instead of bacteria to hydrolyze urea that precipitated as calcite crystal by the availability of calcium ion. Cyclic triaxial shear test under undrained condition incorporated with bender element test were conducted conscientiously on the EICP-treated sands. The parameters study reviewed includes: size of the sand particle, confining pressure, calcite contents, and saturation degrees along curing. The effects of those factors on the shear modulus are systematically investigated and compared. It was revealed that the precipitated calcite wraps the sand particles, which supports simultaneously to the mechanical properties' improvement. The sum of materials needed of urea and CaCl₂ to reach a target of maximum shear modulus can be diminished prominently by reducing the saturation degree along curing. It is also revealed that the formation of the precipitated calcite is more significant than its amount on the strength improvement. The maximum shear modulus (G_max) of the sands treated with EICP increases with increasing in the calcite content, confining pressure, and decreasing in the saturation degrees during curing but the influence of the sands grain size is insignificant.

Currently, the construction of road infrastructure in all regions of Indonesia is highly encouraged, including free roads that connect between provinces. In some parts of the area in East Java, the free roads pass through regions with soft clay so that special treatment is needed. A geological and geotechnical analysis of the nature of the soft soil needs to be conducted to determine the methodology of reducing the compressibility of the soft soil. Based on geological analysis, soft soil is a sedimentation product of the Pliocene – Holocene era. This soil is generally fine-grained, with a high natural water content, and a large amount of organic matter. Several laboratory experiments determined that the soft soil was classified as high plasticity silt with SPT value less than 10 and reached down to a depth of 15.5 m. The value of the undrained cohesion of the soil is around 24.7 kN/m² dependent on the conditions of water content. Estimation of primary consolidation settlement is 2.24m in 18 years. In the soaked-un-soaked CBR experiment, the water content of 37.7% is the residual water content, which is the lowest CBR.

Impacts of material spatial variability usually are not considered in traditional slope stability analyses. However, most geotechnical materials are not uniform inside a slope. The objective of the present study was to evaluate the impact of material spatial variability on slopes in soft rocks. The random field model was used to obtain the material spatial variability. The numerical analyses of slopes in soft rock mass were performed using a distinct element method based program UDEC. After that, Monte Carlo simulation, UDEC, and random field models were used together to analyze the impact of material variability and the slope stability. A series of numerical experiments were performed to understand the effect of joint spacing, joint angle, and size of scale fluctuation (δ). Also, failure types and mechanisms were synthesized and evaluated. The probability of failure became higher as the slope considered horizontal spatial variability of the material. The influence of the horizontal size of δ on slopes without joints was much higher than the slopes with joints. In addition, the slopes with joints yielded fewer failures as δ increased. The results of the analyses could be used for prevention of slope failure, future support system, and geotechnical exploration.

Contemporarily, the use of bacterial Calcite precipitation (bio grouting) is popular as a ground improvement technique for sandy soil. However, this was not frequently applied to organic or peat variety. Meanwhile, on the island of Sumatra, the province with the largest peat terrain is Riau, expanding an area of ± 4.04 million Ha, which is 56.1% of the total mulch land in the region, where Siak is one of the districts, possessing a fairly large portion. Furthermore, numerous problems ensue due to this structure, especially during the construction of infrastructure. Therefore, this study focused on bacterial Calcite precipitation from Baciluus Subtilis, and its effect on the Shear Strength parameters of organic soil, where a special injection system was prepared for inducing the bacterial solution to the samples, which were tested by UCS tool, in order to ascertain shear strength parameter, after 3 days. Moreover, through this research, it is hoped that the technique adopted improves engineering performance, especially in the areas of increasing shear strength parameters of organic or peat soil. Hence, this procedure is suitable and also assists in reducing challenges in construction of infrastructure within Siak district.

The structural health monitoring of a slope against rainfall-induced shallow landslides has become an important issue in Japan with the recent instances of extreme weather. In particular, the early detection of a sudden rainfall-induced shallow landslide is well known to be relatively difficult compared with that of a slow-moving landslide. Thus, local governments or civil-structure management companies provide residents or users with early warning information of a disaster via rainfall-based data. However, rainfall information is not enough to predict the risk of individual slope disasters because it does not directly reflect the soil-moisture condition of a slope. To solve this problem, a soil moisture-based index (iQS) is proposed. The applicability of iQS in a real slope was evaluated using the result obtained by monitoring a real slope during heavy rainfall along an expressway. The monitoring results of the real slope were seen to agree well with the results of past laboratory experiments. This implies that slope deformation owing to the rise in water level does not occur unless the volumetric water content exceeds the IQS of the real slope. Based on this result, iQS can be used for predicting the risk of shallow landslides at an early stage.

In tunnel construction in the city area, NATM method is adopted for construction by the limitation of the construction condition. When classifies roughly in supporting method of construction, there are against the spring water, face stability, ground surface subsidence, cement, water glass and urethane are usually used for grouting material against the spring water, but there is the concern, such as expensive and high load on the environment because of artificial materials. On the other hand, Kaolinite is a natural material, there is less load on the environment, and many merits in the processing of the excavated muck. Therefore, we focused a pressurized clay injection method by using the above-mentioned characteristics and applied this to the construction of the underground. In this paper, the availability of the injection a fluid with a dispersion of kaolinite was discussed to summarize the applicability for controlling groundwater of the saturated sand layer. Specifically, a one-dimensional column test was conducted under the high hydraulic gradient. As a result, it was shown the possibility of effecting of decreasing hydraulic conductivity at less than one-order. Consequently, it is concluded hydraulic conductivity of sand layer was able to be reduced by Kaoline clay suspension.

The Indonesian government, through the Ministry of Public Works and Public Housing, is conducting a housing infrastructure development to encourage economic growth and improve the quality of Indonesian human life. However, the limitations of proper land in the implementations have resulted in the compulsion to build public houses in disadvantaged areas. On November 2, 2018 there was a landslide in a public residential area in the city of Sawahlunto which resulted in 4 houses which are unable to function anymore and 12 others which are damaged and uncomfortable to occupy. In order to investigate the landslide, the field survey has been carried out and the soil samples have been taken and tested in the laboratory. Then, some remedial methods of landslide remedial work at that location were carried out. Furthermore, a number of possible methods are compared in terms of the value of safety against landslides and the cost of the countermeasures. The main criterion is the costs needed for disaster mitigation for this local landslide, which must be smaller than the value of the affected area. If the cost for disaster mitigation is greater than the value of the affected area, then the relocation option may be a wiser choice. However, in this study, the stone masonry is the right choice to be used in the remedial action.

Seasonal changes in tropical regions could cause variations of soil water content, especially in clay soil. Furthermore, there is a significance difference in shear strength between wet and dry clay soil which depends on the plasticity index and the percentage of fine aggregates. Laboratory experiments were conducted to investigate the effect of the plasticity index and the percentage of fine aggregates in clay soil on soil shear strength changes due to water content variation. Soil samples were obtained from five locations in Surabaya City, Indonesia. The soil characteristics were tested in a laboratory to obtain the initial water content, Atterberg limits, specific gravity, and soil size distribution. The next stage was drying the soil samples. Each one was stored at room temperature to reach the determined soil weight. The shear strength of the soil in initial and drying conditions was determined by an unconfined compression test. The results indicated that the lower the moisture contents of soil, the greater the shear strength of soil, and vice versa. Soil shear strength changes up to 52 times within the range of 36% to 72% of moisture content The results also show that the value of shear strength variation depends on the plasticity index and the percentage of fine aggregate.

The design of new and assessment of existing quay walls is subject to large uncertainties. Dealing with these uncertainties is a crucial part of the engineering process. The way uncertainties are addressed has a large impact on construction and maintenance costs and on the reliability ultimately obtained. Especially in the assessment of existing structures the uncertainties can be large. An existing structure allows us to use actual performance information in the assessment, such as the structural response to loading. One way to obtain the structural response is test loading assisted by monitoring. In this research Bayesian updating is used to reduce uncertainties and to more effectively use the obtained measurement data. We present a case study of an existing quay structure along with fictitious measurement data to demonstrate the potential effects of test loading on the reliability of the structure. The results show that Bayesian updating successfully reduces the uncertainty (i.e. standard deviation) of the model prediction. Using monitoring data and Bayesian updating provides a more realistic model of the capacity of the existing quay structure and thus a more accurate reliability assessment. Which may lead to extension of the structure's lifetime or that higher loads can be accepted.

Reliability sensitivity analysis (RSA) is a sensitivity analysis to measure the effect of modelling parameters on the predicted reliability of a system. It can be used for reliability-based design, safety management, etc. The output-classification-based version of RSA compares the failure-conditional probability density function (PDF) of model parameters with their unconditional PDF to measure sensitivity. The main challenge is to estimate failure-conditional PDFs. Usually, these PDFs can be estimated through the failure samples obtained by Monte Carlo simulation. However, practical systems usually have a small failure probability. For such cases, the brute-force Monte Carlo simulation requires a larger number of samples to obtain enough failure samples. Therefore, the computational cost is very high. In this paper, we propose to use subset simulation to estimate the output-classification-based reliability sensitivity index. Subset simulation introduces a series of intermediate failure events which are easier to sample from, and then iteratively samples in each constrained failure region until the target failure event is reached. Compared to brute-force Monte Carlo simulation, subset simulation samples in a direction towards the target failure domain. Therefore, the failure samples can be obtained more efficiently. We apply subset simulation to perform RSA for a carbon dioxide storage benchmark problem. We show that subset simulation can estimate the output-classification-based reliability sensitivity index more efficiently compared to brute-force Monte Carlo simulation.

This paper present several cases in the Port of Rotterdam where both in the design and construction phase several different did not marched as expected. These cases are interesting for both the design as well the construction phase of a project. People will make mistakes however the mistakes describes in this paper have to be judged in time as not always everything was understood during the design and construction and the people of that time still these huge structures.

Despite Japan's significant geothermal energy potential, its geothermal power development has been stymied for decades due to four major hurdles: (1)high upfront cost and risk of exploratory drilling, (2)long lead time due to surveys and environmental assessments, (3) rigorous regulations on national parks, (4)oppositions from local hot spring resorts. The government has been taking measures to accelerate the development with a constellation of supporting policies. But policies cannot break down the conscious barriers that have taken root in hot spring owners; it is in the hands of developers to make constructive efforts for consensus building. The authors, with the role as construction consultant and geothermal developer, are undertaking a geothermal power development project in Hirosaki City, Aomori Prefecture. The primary intent is to realize a vision where local people can benefit from their own geothermal resources, and the authors believe that "sharing the same vision which benefits all the interested parties" is the key to work together with the opposing hot spring owners. In the process of building a trust-based relationship with local residents, the priority has been to hear the needs from the local through dialogue and to think from a larger standpoint.

The track condition in conventional ballast construction is decisively determined by the condition of the sub-ballast and the subgrade. An indicator for the assessment of the track condition is the track modulus, which can be calculated by measuring the rail deflection under load or according to the soil properties. The track modulus describes the ratio between vertical loading and elastic deflection of the sleeper support. This is the first of two papers concerning a theoretical approach to estimate the track modulus of the soil by soil properties. The approach's advantage is to be completely independent from the superstructure condition. Therefore the components of the superstructure along the track axe must not know for calculating the track modulus. Borings with direct ground exploration results and ground penetrating radar measurements are used to determine the soil condition at the track level. After the allocation of the soil properties to each layer, the cone model is used to calculate this average value of the soil properties. Subsequently, the track modulus of the soil is determined by using the average value of the soil properties. Based on the value of the track modulus of the soil, the track condition can then be determined.

The track condition in conventional ballast construction is decisively determined by the condition of the sub-ballast and the subgrade. An indicator for the assessment of the track condition is the track modulus, which can be calculated by measuring the rail deflection under load or according to the soil properties. The track modulus describes the ratio between vertical loading and elastic deflection of the sleeper support. This is the second of two papers concerning a theoretical approach, which allows the estimation of the track modulus of the soil for the layer arrangement of stiff on soft soil layers by using a homogeneity parameter. The homogeneity parameter has to be considered, so that the influence of the layer arrangement, the layer depth and the soil properties can be examined. Borings with direct ground exploration results and ground penetrating radar measurements are used to determine the soil condition at the track level. After the allocation of the soil properties to each layer, the cone model is used to calculate the average value of the soil properties. Based on the value of the track modulus of the soil, the track condition can then be determined.

The ballast gradation has a strong influence on the mechanical behavior of ballast aggregates. Discrete Element Method (DEM) based simulations are performed to investigate the gradation effect of ballast aggregates on their settlement, ballast position rearrangement, breakage rate and void ratio. This is the first part of two papers. In this article, a newly developed ballast random form generator is described. With this generator five form databases of different ballast gradations are established. A box test and its corresponding DEM simulation are usually performed to calibrate and to investigate the mechanical behavior of small-scaled ballast aggregates with different gradations. The ballast stones are simulated by the Bonded Particle Models with the Flat Joint contact model to enable the investigation of the breakage behavior of each ballast stone.

The ballast gradation has a strong influence on the mechanical behaviour of ballast aggregates. Discrete Element Method (DEM) based simulations are performed to investigate the gradation effect of ballast aggregates on their settlement, ballast position rearrangement, breakage rate and void ratio. In the second part of this article, DEM based simulations are performed to investigate the gradation effect of ballast aggregates on their settlement, ballast position rearrangement, breakage rate and void ratio (Part 2). The results indicate that the settlement and the ballast position rearrangement increase with the decrease of the averaged ballast size of a ballast aggregate, whereas the void ratio decreases. Besides, the breakage and the ballast position rearrangement occur mainly with the dynamic loading rather than the static loading. Based on the simulation result, appropriately enlarged ballast stones will benefit not only the stability, but also the hydraulic conductivity of ballast aggregates. The gained result can be used for the optimization of ballast aggregate regarding to its gradation, so that its service cycle can be prolonged.

The objective of this paper is to investigate the effect of nano-calcined clay (NCC) and nano-lime (NL) on some engineering properties of the expansive clayey soil. Three soil samples quarried from three different sites in the south of Syria have been investigated. They were thermally treated up to three different levels (450, 650 and 850°C) for 3 hours. Then, they were ground to have a particle size of less than 100 nano-meter. Three replacement levels of NCC were used, i.e. 0%, 1% and 2%. XRD technique has been employed to detect the phases occurring in the clayey samples before and after the thermal treatment. Pozzolanic activity of the calcined clayey soil has been studied using the modified Chapelle test. Atterberg limits, compaction, free swell, swelling pressure, linear shrinkage, shear strength and CBR have particularly been investigated. Test results revealed the positive effect of NCC. Plasticity index (PI) was reduced by more than 50% when 2% NCC was added to the natural soil. In addition, 0.6% NL was added to further investigate the combined effect of NL and NCC on the properties of the clayey soil. All investigated properties were significantly improved when NCC and NL were added together, i.e. swelling pressure and linear shrinkage values were reduced to less than 15% when compared with those of the natural soil.

In this study the combined uncertainty of a two-dimensional (2D) hydraulic model expanded at 95% confidence level is estimated and the uncertainty budget for the model outputs is attempted to be constructed. It has been shown that many uncertainty sources in the inputs as well as the procedure applied have a significant impact on the accuracy of two-dimensional hydraulic modelling: the uncertainties in the model inputs due to variations in Manning's 'n' Coefficient assigned, the bridge modelling methods, the equation sets; Diffusion Wave and Full Momentum Equations employed and the geometric data sets for the same river system in the Black Sea Region of Turkey are assessed. To estimate an appropriate M'n'C and other model inputs of model for a river system with a wide 2D flow area is a daunting task. Therefore, any attempt to quantify uncertainties in the assigned values must be based on the samples large enough to obtain statistically significant results. To achieve this task, Monte Carlo Method is utilized to estimate the contribution of the likely variations of model inputs onto 'the combined expended uncertainty at 95% confidence level in two-dimensional hydraulic modelling'.

Digital Elevation Model (DEM) is an important component in flood inundation modelling as a part of flood risk analysis. However, Digital Surface Model (DSM) which still contains noises of artefacts is more common to be available than DEM. Then DSM misleads the inundation extent. This study will evaluate a measure to obtain a bare-earth surface (DEM) by developing and applying a workflow to remove the noises from DSM using simple tools available in the GIS computer software. The output of the method will then be used as input for flood inundation modelling of Semarang City in Indonesia. In addition to the main data set of TerraSAR-X DSM provided by Indonesia Geospatial Information Agency (Badan Informasi Geospasial or BIG), two sets of open source digital elevation data from Shuttle Radar Topography Mission (SRTM) and Advanced Spaceborne Thermal Emission (ASTER) are included in this study. The three data sets are processed and quantitatively compared. The results show that the applied noise removal method must be traded off with the lower resolution. Hence, the level of detail of particular flood inundation modelling will determine the required DEM resolution. Different study purposes will lead to different appropriate DEM resolutions to be used.

Governments in Taiwan attach great importance to flood control and disaster mitigation project. Good simulation and estimation in advance are the key point to prevent damages and losses caused by flood disasters. The main objective of this study is to investigate the effectiveness of the Drainage and Flood Control System in Wenshan District completed by the Taipei City Government. SWMM (Storm Water Management Model, US Environmental Protection Agency), a dynamic rainfall-runoff simulation computer program designed for runoff water quantity and quality of single or continuous events in urban areas, is utilized to perform the simulation and analysis in this study. Based on known basic data of facilities such as pipelines, channels, and water storage system, and by setting data related to typhoons and heavy rains from the past records, the runoff at a certain period in each area and the flow and depth in each pipeline are estimated and simulated. By comparing the simulation results with the results before the construction, we can evaluate the effectiveness on the Drainage and Flood diversion system and predict the possible defects. Accordingly, the engineering plan can be modified promptly before the construction to enhance the effect of flood control and disaster mitigation.

"Disasters" such as seismic events, impact or fire loading to structural elements of crucial importance highlight the significance of structural design for robustness. Consequently, exceptional load scenarios are to be considered. The question whether the joints of structures designed according to the current version of Eurocodes have adequate load bearing and defor­mation capacity for such load cases arises. The "alternate load path method" plays a key role in structural design for robustness. By using this design approach, redistribution and distribution of the existing and additional loads, respectively, to the intact structural elements should be enabled after a local failure such as "loss of a column", preventing so the progressive collapse of the structure. In order to pursue the aforementioned goal, sufficient bearing as well as rotational capacity of the joints are required. In particular, for exceptional events, change of the moment's sign in the area of the joints is often to be observed. However, until today, attention has been paid mainly to the response of composite joints under negative moments. Herein, besides this load case, the corresponding one of positive moments is investigated as well as the development of a membrane action that supports the load redistribution but requires a tension force capacity of the joints. Experimental research for the load case "loss of a column" was undertaken on both single composite joint specimens and composite frames. Also, an integrated design method, the beamline method, is analysed and constructional recommendations for design of ductile compo­site joints were developed and are herein presented.

Steel bracing has proven to be a very powerful method to improve the seismic behaviour of reinforced concrete frame structures. In general the steel braces are indirectly connected to the RC frame via additional steel frames that are in turn fixed to the RC frame using post-installed anchors or reinforcing bars. However, this method comes with several shortcomings including increased weight and a disruption of the buildings function during installation. Therefore new connection approaches were developed where the braces are directly connected to the RC frame. One of the most promising solutions is the connection by means of post-installed anchors to connect the bracing to the frame corners. Using this type of connection allows an effective and low invasive strengthening of the structure. In this case the performance of the retrofitted structure is highly dominated by the performance of the post-installed anchors, since the imposed seismic demands are rather high. Therefore it is deemed necessary to assess the anchor performance under seismic actions, especially their displacement behaviour in the post-peak range. The current guidelines for seismic qualification of anchors only provide a force-controlled assessment procedure which is valid for non-structural connections but is not sufficient to obtain the information required for the assessment of their seismic performance in structural applications. A new displacement-controlled approach for the assessment of post-installed anchors under seismic conditions is presented. This approach allows the evaluation of the complete load-displacement behaviour as well as the hysteretic response of the anchors even in the post-peak range. A comparison with existing force-controlled assessment procedures shows that this approach is more suitable for the assessment of anchors used in structural strengthening applications under seismic actions.

Jakarta, which is the largest metropolitan city in Indonesia, has a population of 10.37 million people and an area of 661.5 km². Jakarta's population density of 15,677 people/km² is still far from the ideal population density of 100 people/km². With a high population density, vertical housing development (high-rise residential buildings) is an essential development goal. Indonesian high-rise public housing is focused on fulfilling technical requirements with a perspective only from the designer or developer. In contrast, in the construction of vertical high-rise public housing, a performance-based design that is focused on the user is needed as one of the main stakeholders. Results from survey and partial least square modelling concur that three elements (behavioural, functional and technical) have a 68.3% influence in determining user satisfaction. Each of the elements contributes a positive influence, with the behavioural element as the highest influencer of 44.5%, followed by the functional element at 38.6% and the technical element, which only has 15.4%.These results can also be interpreted as the overall success of the high-rise public housing project.

Concrete edge failure often governs the failure of anchorages, which are installed close to the concrete edge and are loaded in shear perpendicular towards the edge. The design provisions for concrete edge failure given in the current codes are rather limited in applicability. Only anchorages arranged in a rectangular pattern are allowed. For anchorages without hole clearance, the maximum permissible anchor pattern is with three anchors in a row, and for anchorages with hole clearance, a maximum of only two anchors in a row is allowed. Furthermore, for anchor groups with multiple anchor rows loaded in shear perpendicular to the edge, the failure load may be calculated by assuming the failure crack initiating from the front anchor row (EN1992-4) or by assuming the failure crack initiating from the back anchor row (fib Bulletin 58, ACI 318). No design guidelines exist for non-rectangular anchor configurations. In such cases, the design is based on engineering judgement. In this study, experimental and numerical investigations were performed on anchor groups of triangular and hexagonal configurations to study the concrete edge failure. It was observed that the failure crack always initiates from the back anchor row, even in case of anchor groups, where the first cracking is associated with the first anchor row. The first cracking may have an influence on the displacement behaviour of the group, which might limit the design in SLS. However, this is dependent on the displacement behaviour of individual anchors within the group, edge distance, spacing and hole clearance.

Since energy-efficient construction is of great importance, new construction and rehabilitation methods concerning this topic will always be researched. Among these are of course, methods that benefit from solar energy. As part of the BMWi project (Federal Ministry of Economics and Energy) "SWIVT" several options of the energy consumption of residential building blocks will be explored. One of approaches to reduce the energy consumption of the building block and additionally to achieve the energy gain through the solar radiation is an energy garden building block (glass porch). The impact of this energy garden is depicted by means of CFD-simulations (Computational Fluid Dynamics) and will be analyzed in the paper [1]. For this purpose, an energy garden was modeled using an architect drawing and simulated in both winter and summer load cases. For the winter case, the difference in energy consumption between the glass porch and the thermal insulation composite system (ETICS) will be discussed based on the results of the simulation. For the summer, the heat generated by solar radiation in the energy garden can be utilized with the help of a heat pump.

Magnetic-cored dendrimer (MD) is a nano-material composed with the magnetite nanoparticle in the core and dendritic branches developed on the surface of the core. Due to the unique structure and magnetic property of the MD, it has been studied for various environmental applications including the adsorption. With a large number of the terminal group, the poly (amidoamine) dendrimer provides many possible binding positions to various kind of contaminants. It has been reported that the heavy metal adsorption shows different affinity depending on heavy metal species in the aqueous phase. In this study, the MD was synthesized and their binding efficiency experimented with four different dissolved heavy metals of Pb (II), Cu (II), Zn (II), and Cr (VI). The maximum adsorption capacity of heavy metal was in the following order: Pb²+ > HCrO₄- > Zn²+ > Cu²+. The interaction between the MD and the targeted heavy metal was calculated using the density functional theory (DFT). A pseudo-potential code SIESTA model was used. The calculated enthalpy of each metal indicated an agreement with the experimental result. A specific binding position and energies of different heavy metal species were confirmed through DFT calculations. The calculated enthalpy demonstrates structural and dynamical characteristics between MD and heavy metals. The binding preference of MD to a different kind of heavy metal provides useful information for the environmental applications.

Infrastructure development in Indonesia, especially, has moved into swamp areas. Swamps are usually associated with saturated clay and peat soils that are soft and highly compressible. The low bearing capacity and the high excessive settlement are usually solved with piles and pre-consolidation. The remove and replace method with new and better material is sometimes also used. Those methods have really changed the characteristics of the soils and are not friendly to the environment. Some foundation constructions for soft soils have also been proposed, but, in their application, there are technical constraints which are difficult to overcome. Research on the light foundation in soft soils has been carried out to support the light load with a satisfactory settlement. Further studies are carried out to obtain a foundation construction that can support larger loads, but which are still friendly to the swamp environment. The bearing capacity and settlement of foundation is plotted in the graph to formulate the satisfaction indicators of the foundation. In addition, the simple formulation procedures for practical application requirements will be also provided since it is the target of this research for general applications. This foundation is very useful for the sustainability of infrastructure developments that is environmentally friendly.

Retrofitting of existing building in Higher Learning Institution (HLI) has becomes the priority action due to the concern to improve the current energy utilization and indirectly to overall environmental impact. However, prior to retrofitting, it is crucial to evaluate several factors because it's dealing with complex process such issues of design, type of green technologies and system efficiency which regards to decision making in order to ensure the achievement of realistic and rational solutions. This paper highlights a development of decision-making tool for retrofitting of existing building for energy reduction known as Multi-Criteria Retrofitting Building Energy Efficient Building (MCREEB). MCREEB helps to directly indicate the type of practice (best practice, good practice, moderate practice and basic practice) and preferences (exemplary, proficient, apprentice and novice) based on the weightage achieve and the number of criteria selected. Two case studies on building which is M50 Faculty of Civil Engineering and T05 Faculty of Science at Universiti Teknologi Malaysia were used to assess the utilization of MCREEB tool. The assessment considered all relevant retrofitting criteria which identified in this study. The radar chart is cast to portray the most likely influence of criteria during the decision of retrofit. Lighting and occupancy sensor are among green technologies used for retrofitting in the case studies, and its response to criteria of design, economic, environmental, occupants comfort, building physical and technical. This study contributes to the stakeholders in HLI, building industry professional, national or international organization who preferred to ops for sustainable building practices. McREEB provide a way to conduct retrofitting idea through the assessment criteria which would benefit to the actual implementation and aid the decision makers in retrofitting evaluation.

Indonesia is one of the wealthiest botanically countries in the world. There are more than 130 species of Bamboo can be found in this country. Bamboo is a natural raw material which is one of the fastest growing plants that has many advantages as a construction material. We conducted an experimental investigation to study the performance of the precast segmental bamboo reinforced concrete beams with bolted connections subjected to flexural loads. Tests were carried out on three specimens with dimensions of 120 mm x 150 mm x 1000 mm, consisting of one control beams (BK), one precast segmental bamboo reinforced concrete beam with four bolted connections (BS4), and one precast segmental bamboo reinforced concrete beam with six bolted connections (BS6). We found that the load carrying capacity of precast segmental bamboo reinforced concrete beams with four bolted connections (BS4) and six bolted connections (BS6) had a decrease of 57.99% and 55.62% respectively compared to control beam (BK). Similarly, the deflection ductility index of the precast segmental bamboo reinforced concrete beams with four bolted connections (BS4) and six bolted connections (BS6) had a decrease of 49.78% and 46.59% respectively compared to control beam (BK). Also, we observed that the crack pattern developed in the control beam indicates a flexural failure mechanism while the crack pattern developed in the precast segmental bamboo reinforced concrete beams indicates a shear failure mechanism. As a conclusion, this study will significantly contribute to the growing development of research on the bolted connection system in bamboo reinforced concrete members, especially in Indonesia.

Nowadays, system identification of structures has become an important subject in the civil engineering community. The reason is that with a good system identification method, modal parameters such as natural frequencies, mode shapes, and damping ratios can be obtained accurately, leading to an excellent structural health monitoring system. The two systems identification techniques are categorized as frequency-based and time-based domain identifications. In addition, the identifications based on the output-only measurements are gaining more attention from the researchers recently. One of the advantages of this type of identification is that the modal parameters can be obtained without knowing the excitation forces. In other words, it is not necessary to know the input load of the structures. This paper considers output-only identification based on Frequency Domain Decomposition (FDD) and Natural Excitation Technique (NExT) as FDD-NExt. FDD is one of the methods that relies on the output-only measurements such as displacement, velocity, or acceleration, in order to obtain the natural frequencies and mode shapes of the structures. On the other hand, NExT has good ability for determining the damping ratios of structures. This paper aims to apply the FDD-NExT to obtain the modal parameters and the damping ratio of plane frame structures. Two plane frame structures are considered in this paper to show the ability of the proposed method to predict modal parameters and the damping ratio of the structures. The first structure is a one-story frame with 6 degrees of freedom, while the second structure is a four-story frame structure with 48 degrees of freedom. For comparison, Modal Assurance Criterion (MAC) has been used to determine the difference between the modal parameters obtained by FDD and finite element analysis. The results show a good correlation between those two methods.

Pull-out has been proved to occur more often for bonded anchors under tensile loads at high temperatures than at ambient temperature. The existing evaluation method of bonded anchors under fire only covers steel failure mode. Due to the absence of guidelines for evaluating the pull-out of bonded anchors directly exposed to fire, only the evaluation method for mechanical anchors (without resin) is applicable. This paper presents an experimental study on the influence of different parameters linked to the existing evaluation method by means of pull-out fire tests. Additional unloaded fire investigation tests were conducted to compare different configurations of pull-out fire tests. This paper highlights the level of accuracy of load prediction using the resistance integration method based on temperature profiles of bonded anchors directly exposed to a standard ISO 834 fire. Results showed that parameters such as the existence of metallic fixtures on the rod barely influence the predicted load-bearing capacity and failure time. However, parameters such as adopting concrete element temperature along the thickness instead of steel temperature along the embedment depth, and the existence of insulation around the fixture have a greater influence and may result in a false estimation of the load-bearing capacity and failure time.

Structural failure, which can be caused by design miscalculation or changes in the building's function, can be dangerous if left untreated. Consequently, structural strengthening is done by providing steel plates, fiber-reinforced-polymer, or in the traditional way using bamboo fibers. In this study, a numerical calculation for bamboo strengthening using the FEM method is conducted. Bamboo strengthening was installed on concrete beams and attached using mortar. The analysis was carried out with ATENA software dealing with beam specimens, namely Control Beam (BC) and Bamboo-strengthened Beam using M13 and M20 mortar (BB13 and BB20). The materials used are CC3DNonLinCementitious2 and CCD3DBiLinearSteelVonMises for concrete and bamboo, respectively. The concrete and mortar use the fracture concept of a uniaxial stress-strain law and the constitutive model of the bamboo is based on a linear stress-strain law. The results of comparing the numerical and experimental results for the load-carrying capacity ratio are 0.96, 0.90, 0.77 for BC, BB13, and BB20, respectively. The crack pattern of the specimens shows that collapse is by flexural cracking starting from the mid-span. This is in accordance with previous laboratory results. In conclusion, the analyses using ATENA program and experimental methods show the appropriate results.

The increase in the number of terrorist attacks have shown that the effect of blast loads, such as the Friedlander blast load on elements of a building structure is a serious matter. Their effects on the structure should be taken into consideration in the design of the structure's element. The objective of this study is to numerically analyze the blasting effect on stiffened orthotropic concrete plates within the elastic range of its material. The effects of the stiffener configuration, the location of the localized blast load as well as the influence of the thickness to the vertical deflection of the plate are solved numerically by using the two auxiliary equations in the x and y-directions. The analysis yields the vertical deflection versus time relationship which can be used to determine the stress distributions and the maximum stress value of the plate. This paper introduces the effect of the blast load on the orthotropic plates and essential techniques used to increase the capacity of a structure's element to provide protection against explosive effects.

Structural strengthening with Carbon Fibre Reinforced Polymer (CFRP) confinement has been widely used in civil engineering applications. However, the use of CFRP has always triggered environmental and sustainable issues due to its hazardous manufacturing and disposal process. By using partial CFRP confinement, the use of CFRP as the strengthening material could be reduced. The circular hollow reinforced concrete column is commonly used in seismic zones due to its self-weight reduction and better structural efficiency of strength/mass and stiffness/mass ratios properties. However, up until today, the understanding of circular hollow reinforced concrete column behaviour still lacks, especially with CFRP partial strengthening confinement. Therefore, this paper is testing a 6 full-scale circular hollow reinforced concrete columns with 2 m height, 250 mm of outer diameter, and 110 mm of inner diameter. The behaviour of the unconfined circular hollow column will be compared with partial CFRP confinement under axial load. The circular hollow reinforced concrete column with partial CFRP confinement is proven to be able to strengthen circular hollow column effectively through this study.

This paper considers optimum parameters tuned mass damper (TMD) as a vibration absorber with zero damping. Generally, tuned absorbers with damping have been considered to be applied to the structures. While adjusting damping constant produces additional complexity in real applications, this paper investigates the use of absorber with zero damping. The properties of the absorber to be designed then is reduced to only its spring constant, while the damping is set to zero throughout the design process. To optimize its spring constant, genetic algorithm (GA) with real coding is utilized. With the optimized spring properties obtained from the optimization, the performance of structures is then investigated under several earthquake excitations. The performance of the optimum absorber with zero damping is also compared with the one when arbitrary damping presents in the absorber. The simulation results show that the performance of the absorber with zero damping is smaller compared to the one of absorber with damping. However, the response of absorber with damping tends to decrease when time increases.

In this paper, the concrete gravity dam built 40 years ago was partially damaged by the M=7.3 Chi-Chi Earthquake in central Taiwan in 1999. The elastic wave tomography method was applied to identify the safety conditions of the repaired dam in 2010. The resulting velocity profiles showed that the total structure conditions were accepted as a good to questionable condition. The filled materials and cracks existed in some dam components. Seven years later, the updating tracing investigation revealed that the pervious detrimental zones were spatially extended and associated with time. These testing results were also consistent with the findings from the ground penetrating radar inspection.

The velocity tomography inspection, including modified cross-hole sonic logging and ultrasonic velocity tomography methods, was introduced to detect the reinforced concrete pylons of a pedestrian suspension bridge in northern Taiwan. At the first stage, the modified cross-hole sonic logging method was employed to rapidly identify the positions of gross anomalies on the shafts and horizontal beams of the bridge pylons. The possible anomaly sections, usually with a relatively low velocity, were chosen for the ultrasonic velocity tomography testing in order to finely determine the velocity spatial distribution image and localize the anomaly positions. The on-site inspection results indicate that the lower horizontal beams and connection zones with concrete shafts on the pylon were significantly attributed to a questionable level (i.e., velocity of 3,000~3,600 m/s). These structural detrimental positions have been provided for the bridge agency for the further improvement plan on the bridge pylons.

Most regions in Indonesia have the potential for earthquakes, including Mandailing. Traditional wooden house of Mandailing was established without the expertise of an engineer and architect. The aim of the study was to identify the wooden structures against seismicity to obtain an efficient and contextual wood construction for earthquakes. Therefore, it is important to observe and analyse the structure of buildings through seismic approaches and alternative solutions to the sustainability of construction. The research method was an experimental using SAP2000 simulations. It was to identify the performance of columns and beams as the main structures that require reinforcement and experience friction. The data analysis showed that the building had a mass of 355.484 kN with a static shear force of 150.0142 kN and a dynamic shear force of 693.274 kN, while the vibrating period of the Mandailing traditional wooden houses structure had a T = 0.94267 seconds value. In other words, the SAP2000 modelling results illustrate that the displacement which occurs in buildings with an earthquake scale factor of 10 is still within the safety limits. Thus, the buildings are flexible to earthquake movements, and damages in the buildings can be minimized.

Seismic performance of RC frame structures was investigated by creating 3-D models of the frame with additional solid RC infill wall along the height of Honolulu Building prescribed in FEMA design examples. Layered-shell element (LSE) was used to model the infill wall and gap element was introduced at the interface between the wall and the bounding frames. The modelling technique was validated against test results reported in the literature prior to its application on the 12 story building. The push over curves of all models were compared to obtain the most efficient model that conform to the strength and stiffness requirement of the seismic codes of Indonesia. The results showed that the non-linear behaviour of RC frame with RC infill wall can be modelled accurately using LSE and gap element. The RC wall addition improved the strength, stiffness and performance of the frame significantly. The most efficient model was that with infill wall up to the first 4 story levels in which, the performance of the structure improved from collapse prevention to immediate occupancy.

Orthotropic Levy-type solution plates considering shear deformation were solved by using the Spectral Element Method (SEM). In SEM, the exact solution of structural dynamic related problems can be solved by using the frequency-dependent shape functions. The solutions of SEM are accurate in decreasing the amount of Degree Of Freedoms (DOF) to discard the cost and computational disadvantages in the Finite Element Method (FEM). This study investigates the free vibration problems of orthotropic Levy-type solution plates solutions based on the two variable Refined Plate Theory (RPT). SEM for orthotropic Levy-type solution plates in the frequency domain was formulated to solve free vibration problems. The differential governing equations of the orthotropic plate element in SEM are formulated into the form of transcendental stiffness matrices. The boundary conditions of the spectral element model consist of four edge-type DOFs at each side of the orthotropic Levy-type solution plates. The natural frequencies of the plate are calculated by means of the Wittrick-Williams procedure. The numerical investigations are presented to show the accuracy, efficiency, and effectiveness of SEM without any discretization scheme.

A new combined rings and horizontal steel pipe as hysteretic dampers for seismic resistant steel structures have been developed. Simulation studies for various models of the dampers have been carried out under cyclic shear loadings. In each model, different strengthening strategy applied to the combined rings and horizontal steel pipe damper was explored. The chosen model among simulated dampers experienced extensive yield under different cyclic loadings. The specimens of the chosen model have been tested using the same four different cyclic shear loadings, which are ultralow-cycle fatigue (ULCF) loads representing extreme earthquakes. At the end of each testing, all tested dampers experienced ductile fracture. The test results showed all dampers have a stable hysteretic response under ULCF loads. All dampers exhibit excellent ductility represented by many plastic cycles before failures. If enough number of dampers are installed in building structures, the combined rings and horizontal steel pipe dampers can be used as the seismic energy dissipating devices for steel structures.

Modern requirements of engineering practice in tunnel construction are related to the problems of strength and the identification of reserves of bearing capacity of tunnel lining. The achieved success in creating rational reinforced concrete structures of tunnel linings is largely determined by the results obtained in the field of mathematical and mechanical modeling of deformation processes. Reinforced concrete large-sized building structures constitute the main structural elements of the Tashkent underground tunnels in Uzbekistan, as reinforced concrete under proper conditions gives a significant technical and economic effect, reducing the time and cost of construction. Experiments on the bending of reinforced concrete beams with a gradually increasing load indicate various stages of the stress condition. To achieve the most economical consumption of materials, it is proposed to calculate structures for the forces that act under breaking load. This paper presents a method for calculating the lining of reinforced concrete tunnels of the Tashkent underground based on the more accurate assessment of the fundamental properties of reinforced concrete that determine its behavior under external load.

In seismic analysis of building, infill wall is usually modelled as non-structural elements and, hence, are not taken into account in analytical models. In general, engineers and scientists model these widely used structural system of masonry infilled reinforced concrete frame by considering the infill wall as load applied to the open confining frame. The presence of masonry infills, however, may significantly alter both the stiffness and the strength of the overall structural frame system. This present study aims to evaluate seismic performance of this type of building by developing fragility functions of the structure. Masonry wall was modelled as diagonal strut within the concrete frame. The masonry constituents and its composite properties were determined for the model. Then, the structure was subjected to incremental static lateral loading while adaptive pushover analysis was utilized to predict the response of the structure. As the damage states were defined from the spectral capacity curves, the fragility functions were developed for the structure. Effect of masonry wall included in the analysis was then compared to the results of open frame. The result of the eigen value analysis shows, the period for modelling a structure with an infill wall is smaller compared to modelling a structure without infill wall (open frame). This shows that the existence of infill wall elements in modelling increases the value of structural stiffness so that it reduces the period of the structure. Whereas, the results of the fragility curve in both structural modelling show that at some level of damage, the probability of damage for modelling structures with infill walls is smaller when compared to open frame. Realistic and rational results is presented in this work which show that modelling masonry wall with compression strut is beneficial.

The paper presents a numerical study conducted using in-house code for 2D transient heat-transfer analysis. The code solves the governing differential equations for transient heat-transfer using finite difference scheme and iterative solver. The code takes the information related to loss of concrete cover as an input and update the thermal boundary conditions (moving BCs). The validation of the code against experimental results available in literature has been presented. The paper also presents a parametric study to investigate the effect of corner spalling on predicted reinforcement temperatures for a beam. The parameters investigated includes: depth of lost concrete cover, time at which the cover is lost and fire exposure (ISO-834 and design fire). As expected, higher reinforcement temperatures were observed for higher loss of corner concrete corner cover but the effect of smaller cover loss (28% diagonal cover) was negligible. It was also observed that for longer fire exposures, depth of lost cover is more important than the time at which it is lost. In case of design fire exposure, it was observed that; large cover lost during heating-phase results in a higher temperature, which still occur during the cooling-phase but earlier as compared to the reference case.

The aim of seismic design is not intended to make earthquake-proof structures that will not experience any damage even during a strong earthquake; such structures will be too costly. However, controlling the damage to the desired level is a necessity for buildings with a particular purpose such as hospital, fire and police station, nuclear facilities, buildings that contain hazardous material, and other building that is critical for emergencies and defense. In this paper, a four-story steel frame, both with and without hysteretic steel damper are investigated in order to account the effect of stiffness ratio, and SR (ratio between steel damper and braces stiffness to the bare frame stiffness) in the global structural damage. For these purposes, three ground motions which are compatible to the design spectrum response in the Indonesian building code were selected to be applied to the structure with a stiffness ratio (SR) of 2, 3, 4 and 5 using a non-linear dynamic time history analysis. In this context, the damage index based on the works of Park and Ang is used as the criteria to define global structural damage, while story drift index is used as the criteria to measure the seismic performance level. The results demonstrated that the use of steel damper not only enhances the seismic performance, but it also reduces the damage index of the investigated structure. Furthermore, the damage index and story drift index are influenced by the stiffness ratio, in which the stiffness ratio of 4 (four) provides the smallest damage index and inter-story drift index. Moreover, the damage index and inter-story drift index were also affected by ground motions characteristics.

In the present paper, the safety reduction in anchor groups composed of cast-in place headed anchors was experimentally investigated. In particular, groups of two anchors were installed in concrete members designed such that one of the anchors was located in a crack and the other one in plain concrete. The samples were loaded in tension, thus simulating a connection with clamped rotation under both monotonic and cyclic conditions. The results are commented and discussed demonstrating how the presence of uneven crack distribution could lead to a safety reduction, which should be properly taken into account in the design of anchor groups.

The paper presents a numerical study on the response of RC columns under fire. The numerical studies deal with both: during fire (fire rating) scenario and after fire (residual) scenario. The results highlight the importance of Load-Induced-Thermal-Strains (LITS) for predicting the Fire Rating (FR) of RC columns. The predicted temperature variation across the cross-section and axial deformation of column with time are in good agreement with the experimental measurements available in literature. The importance of considering cooling phase of fire for evaluating the behaviour of RC columns has been emphasized. Because of the peak temperatures occurring during the cooling phase and the additional damage due to cooling, the column may also fail during cooling period. The effect of exposure duration on the residual axial load carrying capacity of RC columns has also been discussed. The presented numerical studies using 3D fully-coupled thermo-mechanical model for simulating the behaviour of axially loaded RC columns during the complete fire hazard situation, shows its capabilities to realistically account for different strain components and damage components occurring during different phases of fire hazard (viz. heating-phase, cooling-phase & residual-state). The model uses temperature dependent microplane model for concrete and classical von-Mises plasticity models for reinforcing steel.

The available design rules for anchor channels with channel bolts were developed on the basis of the design rules for fasteners installed in conventional concrete. Recently, also more advanced reinforced concrete types became popular, e.g. fibre reinforced concrete for the production of prefabricated tunnel elements. The existing design rules for fasteners including anchor channels with channel bolts do not cover fibre reinforced concrete. To study the load-displacement behaviour in tension and shear, exploratory tests have been carried out on anchor channel-channel bolt-systems cast in plain and fibre reinforced concrete. The test results demonstrate a superior performance of channel bolts installed in anchor channels which were cast in fibre reinforced concrete if compared with systems cast in plain reinforced concrete.

A cycle of heating and cooling can cause gradual chemical changes in reinforced concrete after a fire and these can affect the strength of the concrete. The study aims to analyse the deflection and damage of post-fire concrete beams. The method of study used numerical and experimental analysis on reinforced concrete beam models 1250 mm in length, with a cross-section width of 100 mm and height of 200 mm. The combustion of the specimen was carried out in a brick furnace for a duration of 30 and 60 minutes with an average combustion temperature of 930 and 926 °C. The flexural strength test of the post-burn beam was carried out using a load cell and measured using LVDT at room temperature. The results showed that the deflection that occurred on reinforced concrete beams burned for 30 minutes (BN30) resulted in increased beam deflection by 7% compared to the unburned concrete beam model (BN). Similarly, the concrete beam model which was burned for 60 minutes (BN60) resulted in a 22% increase in beam deflection compared to the unburned concrete beam model. Also, there is a sloping pattern in the relationship curve between load and deflection with increasing duration of the combustion time. This condition is due to a 62% decrease in the load received by the beam when the beam burned for 30 minutes (BN30). Likewise, when the beam burned for 60 minutes (BN60), this caused a 72% decrease in load compared to the unburned concrete beam model. Thus, the duration of fire combustion in concrete beams significantly affects the strength of the reinforced concrete beam.

This paper presents the results of a study on trusses which are need to satisfy optimal conditions, i.e. the lowest Cost possible cost with maximal performance. The trusses considered were statically indeterminate steel structures with a multi-system loading. The cost is represented by the material volume of the structure and the maximal performance is reflected by the high working stresses reflect the maximum performance within allowable stress limits. The material strength was modeled as a random variable with a Log Normal distribution. The structures are also required to meet a failure probability of Pf =10^-3, which may occur locally within the elements as well as globally on the structure as a whole. The complexity of optimization problems depends in general on the number of the considered variables. The larger the number of variables considered, the more complicated becomes the solution process. Therefore, cases of single variable elements such as multi variables ones were considered in this study. Optimization problems are usually solved by applying iterative procedures, frequently resorting to mathematical programming. In these procedures the process usually converges to unreliable solutions; it even may completely bogged down with no solution. To circumvent this problem, iteration was carried out by applying Genetic Algorithms where the process proceeds in a stochastic manner.

Post-installed anchorages or reinforcements using bonding adhesives are invariably used in the present day construction industry. Although, various attempts to develop a generalized theory for design and analyses of adhesive anchorages have been made, the actual anchorage behaviour is still considered to be dependent on the adhesive product in use. The creep behaviour of adhesive anchors were investigated again intensively after several failure were observed. Several research experiments in this regard are performed by different researchers to establish a new procedure of failure accounting the creep effects of adhesive anchors. This work discusses the results of an experimental program undertaken at the University of Stuttgart, for establishing the time-to-failure behaviour under sustained loads for two different adhesive anchor products. The complete test program included reference pull out tests to evaluate the ultimate capacities. Sustained load tests were performed for the load levels corresponding to 85%, 75% 65% and 55% of the ultimate capacity observed in the reference tests. The test program also included sustained loading tests at different temperature conditions like ambient temperature (23°C) and moderately high temperature (43°C). A comparison of the creep behaviour for standard and sub-standard installation condition was also included in the test program to see the effect of a reduced installation cleaning process. In this paper, the results for standard installation with ambient temperature of 23°C are used to demonstrate the sustained load effects in the framework of time-to-failure behaviour. The possibility of arriving at a safe load level which can be sustained throughout the design lifetime of 50 years is discussed using the time-to-failure curves.

The existing anchorages in reinforced concrete structures may need strengthening due to an increase in the applied load during its lifetime. In certain cases, due to limited dimensions of the structural member (e.g. concrete slab or beam), the size of the anchorages that can be used is also limited and the standard design of anchorages may not be enough to provide required load-carrying capacity. In these above-mentioned cases, a method to strengthen the anchorage may be needed. In the present work, it is attempted to develop a method for strengthening of anchorages under tension loads by using post-installed reinforcing bars. Tests were performed on anchorages using bonded anchors (single anchors) without and with different configurations of post-installed reinforcement for strengthening. The main objectives were to investigate the influence of the reinforcement arrangement on the ultimate load capacity and on the load-displacement behavior of the anchorages. The bonded anchors were selected considering the ease of installation and freedom to choose the test parameters. The tests were performed on anchorages away from the edge. The test parameters were determined in a way that in the case of reference tests, concrete breakout was the dominant failure mode. The reinforcement was placed relatively close (with a distance of approx. 0.4·hef) to the anchor. The results clearly show that the post-installed reinforcement can result in a considerable increase in the load and deformation capacity of the anchorage. Depending on the amount and arrangement of the reinforcement, a change in the failure mode from concrete cone breakout to strut-failure could be observed. It was also shown that for the same amount of reinforcement provided, the arrangement of the reinforcement had a considerable influence on the effectiveness of the strengthening. To understand the mechanics better, in certain tests, strain gauges were applied on the reinforcing bars, which showed the interaction between the contribution of concrete and that of reinforcement in resisting the applied loads.

This paper studies the influence of steel fibre distribution and the flange thickness on the flexural behaviour of steel fibre reinforced self-compacting concrete (SCFRC) ribbed slab. Six (6) ribbed slab panels that were fully and partially reinforced with steel fibres with the dimension of 2.8 x 1.2 m were fabricated for the purpose of this study. Variations were also made in terms of the flange thicknesses, i.e. 80, 100 and 120 mm. All slab panels were loaded under four-point bending. Hooked end steel fibres were incorporated in the mix with the volume fraction of 1% (80 kg/m³). The ultimate load of the fully reinforced panels showed 15-52% higher values than partially reinforced panels. The highest difference was exhibited by the sample with 120 mm flange thickness. Significant difference was observed in the fully reinforced samples, with the 120 mm sample showing the highest ultimate load. The influence was however less imminent as for the partially reinforced sample. The load-deflection curves for the SFWS panel showed smooth deflection hardening curve while SFT samples exhibited steeper curves. As a whole, it can be concluded that better performance was demonstrated by the fully reinforced sample with the highest flange thickness.

The punching shear resistance and behaviour of self-compacting fibre reinforced concrete (SCFRC) of flat slab were studied in the previous research. Currently, there is limited information available on the ribbed slab, without conventional reinforcement, and using SCFRC as the main material. The extensive convolution of the punching shear behaviour within the concrete and structure itself, and insufficient appropriate test method ascribed to the conventional reinforcement are being used. Hence, the testing setup, to examine the punching shear resistance and behaviour of the ribbed slabs by using SCFRC, was carried out. The substantial experiment on the SCFRC ribbed slabs, prone to punching shear failure, with the designed test arrangement was employed. The association between the punching shear load and the angle of the shear plane, the critical value of the basic control perimeter and the failure mode were studied and analysed from the results obtained. This research gives insight into the punching shear capacity of SCFRC ribbed slabs. The results exemplify and accentuate the advantages of using SCFRC, compared to the normal concrete in structural designs. The punching shear test presented here has established itself as a suitable procedure for testing SCFRC, and potentially, other fibre reinforcement composites.

Concrete damage (cracks, voids and delamination) significantly influence initiation and propagation phase of reinforcement corrosion. The three methods are combined in the framework of this research: (i) on-site testing on concrete bridges, (ii) application of an advanced numerical model for service life prediction on existing structures and (iii) laboratory experiments on permeability of cracked concrete. The aim of this research is to determine the mutual interaction of material, structural, environmental and climate performance indicators under following degradation mechanisms: chloride induced corrosion of reinforcement in concrete and concrete cracking due to mechanical and non-mechanical loading. The broader aim is to predict bridge service life more precisely as a base for establishment of an optimal bridge quality control plan. The focus of the paper is application of on-site testing on existing bridges. Influence of cracks in concrete on reinforcement corrosion on existing structures can be determined by application of non-destructive testing, not only by measured values but also to define area of structure on which a crack has impact.

Bridge engineering world practice has showed that implicit method of service life prediction, relying on sufficient quality and depth of concrete cover, do not guarantee a 100- year structure lifetime without major, complex and expensive repair works. Bridges exposed to harsh combination of mechanical (static, dynamic, cyclic loading) and environmental (sea salts, de-icing agencies, freeze - thawing cycles, etc.) actions are particularly vulnerable. Two such case studies: Krk Bridge and Maslenica Bridge located in aggressive maritime environment will be analysed in the paper including in-service performance and comparison between measured values on bridges and numerical results obtained by two numerical models for service life prediction: the 3D chemo-hygro-thermo mechanical (3D CHTM) model implemented into the finite element code MASA and the Life-365 model. Both models are capable to realistically predict chloride content in concrete after long-term exposure to seawater. However, the 3D CHTM model, which considers cracks and damage in concrete, anticipates the beginning of steel reinforcement depassivation much more precisely than the other model which doesn't take concrete damage and cracks into account.

Sustainable development issues have become very important in the recent years, and the increased sensibility on sustainability of civil engineering structures are inducing to set the attention in recycling operations, also in the context of building materials. Concrete is the most used construction material in the world and its production requires a considerable demand of energy and raw materials, inducing significant gases emissions and huge quantity of natural materials and non-renewable resources exploitation. Electric Arc Furnace Concrete (EAF concrete) is a kind of recycled concrete in which its aggregates are the by-product of steel and iron producing processes, the so called Electric Arc Furnace (EAF) slag: while its environmental positive effect is easily understandable and intuitive, its effective usefulness and reliability in the building field is more difficult to accept. From the literature data, it seems that EAF concrete presents higher values of compressive and tensile strengths and modulus of elasticity than the natural concrete ones, and this might induces one to think that a higher structural reliability could be expected. However, it is worth recalling that this material is characterized by also a higher self-weight, thus, increasing the dead-load values. Hence, in this study, a reliability-based analysis of the structural load-carrying capacity of EAF reinforced concrete (RC) elements is carried out, through a fully probabilistic approach based on Monte Carlo simulations improved by Latin Hypercube method (LHS). The analysed RC elements are designed according to the Italian current construction code, and then, considering all the uncertainties included in the random variables definition, failure probability and relative reliability index are estimated and compared to the reliability of the same RC elements with natural concrete. Results indicate that, for the analysed cases, when EAF slag is used as coarse recycled aggregate, it is possible to guarantee the same reliability level than in RC elements realised with natural concrete.

Due to research activities on the topic of concrete mixtures during the last decades concrete compressive strength could be increased significantly. At the same time the lifespan of concrete structures has been continuously extended. Therefore, the fatigue behavior of modern High Performance Concrete (HPC) becomes more important with respect to service life. Previous studies on normal strength concrete have shown that the number of cycles to failure under pure compressive cyclic loading mainly depends on frequency and amplitude. An increase of the loading frequency leads to a higher number of load cycles to failure. Recent research work shows that the humidity of the specimen is also influencing the fatigue behavior of concrete. Conditioning of the test specimen to high humidity led to significant lower fatigue life. Other research activities on high strength concrete point out the effect of the loading frequency on load induced heat effects of the concrete. The experimental study presented here aims on the influence of the humidity on the temperature development under fatigue compressive loading and on the number of cycles to failure. It comprises three fatigue test series at a test frequency of 10 Hz with sealed cylindrical specimens of the same concrete with different degrees of humidity. In addition, destructive and non-destructive tests were carried out on damaged and undamaged concrete.

This paper presents the intensity crack zones of a damaged reinforced concrete (RC) beam with the size of 200 mm x 300 mm x 1500 mm repaired with an epoxy injection under monotonic loading. The acoustic emission (AE) technique concurrent with three-point loading was used to monitor the behaviour of the beam. The intensity analysis based on AE signal strength was carried out on CH6 and CH7 at each crack mode. It was found that the intensity plots are well matched with the progression of the crack in the beam. It is inferred that the intensity zones can be utilised to characterise the damage in the beam.

Distributed Optical Fiber Sensors (DOFS) are strain measuring tools whose potential related to the civil engineering field has been discovered in the latest years only. A unique utility lies in the possibility of bonding these extremely thin sensors to steel reinforcement bars which will later be embedded in concrete elements (RC) in order to monitor its mechanical strains. The present paper presents the results of an experimental campaign that saw the tensing of two RC tensile members (ties) with DOFS-instrumented steel rebars providing strain readings every 7.5mm. Their cracking behavior allows to gain insight on the steel rebar's strain profile when surrounded by cracking concrete. The described results are novel as measurements that are accurate, completely distributed, experimentally extracted, both before and after concrete cracking, have been impossible up until now. The internal strain measurements are additionally integrated with an external Digital Image Correlation (DIC) monitoring which provides data on the displacements and strains of the members' surfaces. The present research represents the beginning of an in-depth experimental campaign aimed at providing reinforcement strain data for multiple loaded RC ties encompassing different geometrical features (concrete cover, reinforcement ratio, bar diameter).

In the paper, the performance of two phase change materials (PCMs) is evaluated numerically and experimentally. Technical requirements, size limitations and time response of the PCM present crucial boundary conditions when choosing the right material and storage type in the residential sector. The latent heat thermal energy storage system analysed in this paper is a modified shell-and-tube type of heat exchanger using paraffin wax RT-28-HC and a bio-based substance PureTemp28 as phase change materials with heat storage capacity of 255 and 190 kJ/kg, respectively. Their phase change transition temperatures are between 27 and 29 °C which makes them suitable for domestic applications together with underfloor heating and heat pump units. In order to properly validate the simulation results, a corresponding machine with the similar initial and boundary conditions has been set up. Additionally, to account for all possible impacts on the performance of the PCM, thermal storage unit was equipped with 24 radially distributed temperature sensors, a pump with variable rotational speed and a water supply machine that operates in temperature ranges from -50 to 150 °C. The results from the experiment exhibit very good correlation with the numerical simulations concerning the charging and discharging times.

Global warming is a result of greenhouse gas emission from various sources, such as industrial manufacturing, transportation, and construction activities. Among these, construction activities further involve the destruction of the natural environment, which should be protected for ecological balance. During construction, the natural environment should be protected by preserving the natural scenery while ensuring safe and rapid construction. To achieve this, the construction structure needs to be designed with the features of light weight, high efficiency, and safety using deployable structures. Deployable structures are superior over general structures because they can be extended in any area within a few hours and have less impact on the natural environment of the construction site, thus providing an alternative choice for environmental protection and conservation. In a deployable structure model, deployment and truss structures are combined using the scissor mechanism concept. However, the structure is required to remain in a stationary condition. Therefore, this study investigates the equilibrium theory of the scissor structure and presents the methodology of a new bridge construction method.

The seismic hazard analysis requires an estimation of ground motion intensity where the process needs to use a compatible ground motion prediction equation or GMPE, which provides ground acceleration estimates in a function of earthquake magnitude and distance. Hence, the effect of current equation often does not accurately represent the earthquake condition in East Malaysia region. In this study, the characteristics of low-to-moderate databases were used and derived by regression analysis in terms of horizontal peak ground acceleration (PGA). The appropriate GMPE design for East Malaysia is based on the ground motion records compiled from strike slip earthquakes that occurred within 10 to 1,350 km. This earthquake data is based on actual data recorded at a broad range of magnitude levels within a wide range of distances. The new equation is used to predict the PGA value throughout East Malaysia by probabilistic method. PSHA is a method to analyse seismic hazard assessment using probability concept by considering the uncertainties of the size, location and rate of occurrence of earthquake and the variation of ground motion characteristics. The four well-known existing attenuation functions are evaluated with current equation to highlight their limitations in magnitude and distance. With a more complete collection of earthquake databases, GMPE has become more reliable. The GMPE of peak ground acceleration for low-to-moderate earthquake at long distance was found to be logarithmically distributed. The equation provides ease in both implementation and interpretation of physical parameters with a comparable standard deviation.

Cellular Lightweight Concrete (CLC) brick is a material composition for wall building made of Portland cement, water, and fine aggregate blended with a foaming agent. The weight of the brick is light due to the air cavities formed in the CLC brick. The number composition of sand and cement in the CLC brick could improve the strength of the bricks. Thus, it is essential to find out the sand and cement consumption in order to improve the rate of brick strength. The study aims to improve the strength of the CLC bricks with the different composition of the material and to find out the index properties of the CLC bricks with the variable component of the materials. The study used an experimental work in the material laboratory with two variations of the material composition. The first variation is mixing concrete for the ratio of cement and sand of 1:2, while the second variation is mixing concrete for cement and sand ratio of 2:3. The wet density of the CLC brick is about 800-900kg/m³, and the average compressive strength test was conducted at ages 3, 7, 14, and 28 days for each test. Three identical specimens were prepared for each test. The study resulted in the 28-day strength of the CLC brick with a mass ratio of cement to sand 1:2 of 0.52 MPa, and the strength of the CLC brick with a mass ratio of cement to sand 2:3 was 0.68 MPa. The first variation was lower by 24.5% than the second variation in terms of strength. The higher cement consumption used into the mixed can make porosity of the specimen decrease, and then the strength of the specimen will improve.

Bridges play an important role in transportation network. After an earthquake, bridges must remain functional. To reach this goal, vulnerability study must be conducted. The aim of this study is to develop a vulnerability index method for bridges. The most important parameters influencing the seismic behaviour of bridges are identified, and a seismic vulnerability assessment model is developed using the analytical hierarchy process (AHP) to quantify the contribution of each parameter. Using the developed model, several bridges are treated and the obtained results show a good adequacy with in situ observations.

Ground anchoring is a popular method to stabilize the slope. It is essential for stability evaluation to measure the tension value of anchor from installed load cell. In this paper, a wireless anchor load measuring system is proposed for continuously on-site slope stability monitoring. Each anchor load cell is connected to a MCU-based acquisition unit and become a wireless IoT end-device. This system is scalable so the sensor deployment will be much more flexible than that in conventional data acquisition system. The excitation circuit, signal amplification and analog-to-digital conversion are completed by a small-size device next to the anchor so that very low-noise result can be obtained. Each measurement consumes less than 10mA·s so this device can be drive only by a 55mm*70mm*40mm solar power module. Verified by almost 3-year's on-site test, it is confirmed the proposed monitoring system can continuously capture and send one measurement per minute to the cloud server without any other electric power. The experimental and on-site test results show the practicability of proposed system and its reliability of long-term measurement. It has very high application potential on real-time slope stability monitoring by collecting and analyzing the load values of all installed anchors.

Sustainability, i.e. among other things climate change and resource consumption in the product development phase, have to be increasingly taken into account. The primary energy demand of products and their influence on the greenhouse effect can be scientifically analysed through life cycle assessments. For this purpose, all product, energy and material flows must be recorded in each individual product life phase. If, for some reason, no identifiable data is (yet) available, assumptions must be made whose uncertainties may later lead to deviations in the results, some of which are difficult to assess. This can pose a major problem, as many parameters have not yet been defined or will change in the early development phase such as the production scale. In order to be able to compare the products correctly with already established products, however, the possible changes must also be considered comprehensively. An extension of the established methodology by the concept of interval arithmetic makes it possible to determine the entire spectrum of all environmental impacts potentially occurring through the product, since the existing uncertainties are considered directly in the balancing. This is illustrated by the example of an aerogel-based thermal insulation composite system, the insulating material of which is evaluated.

Uncertainties occurring in engineering are usually dealt with by means of statistical validation. Most value assignments are of statistical nature and thus only valid in a specific statistical way. This fact is, in most cases, only implicitly apparent but nevertheless almost always present. In green engineering this is not true. The calculation e.g. of life cycle assessments (LCAs) is generally based on a vast number of values. These data either cannot be validated in a statistical sense at all or they are too insufficient to be usable for statistical analyses. This means that final results in this field cannot be declared as trustworthy in a way that is common in engineering. In this paper, the method of interval arithmetic is proposed as a way to circumvent this severe epistemological problem. The consequences of the suggested approach are illustrated utilizing two typical examples: (1) Different reliabilities concerning theories for greenhouse effect influences of various chemical emissions on the greenhouse effect and thus on the global warming potential and (2) Situations, where one specific production site differs heavily from the average of the dedicated industrial sector. Computational implementation of the considered concept is briefly discussed. It is shown that misleading results, which may be quite common in this field, can possibly be avoided in the proposed way.

This paper presents the experimental study on the control of the heat of hydration of mass concrete using the concrete bio-admixture, bioconc. The basic issue of mass concrete is thermal cracking, because of the heat of hydration of the cement content in mass concrete. This paper reports on the research results of using the concrete bio admixture, bioconc as a micro filler. To control the heat of hydration of mass concrete the cement content was reduced significantly up to 40 percent. The product is called bioconc low heat concrete. In order to control the researched object, it was compared with: pre-coolingmasscon and fly ash based low heat masscon. There were three parameters to be compared for asessing the product: hydration heat control effectiveness, cost of raw materials and the environmental impact. In this research, the concrete was made with fc' 25 and the size of the mass concrete mock-up was 1000x1000x2500 mm³. Research result written in series of following data: the peak temperature, duration to reach peak temperature, thermal gap between core-edge off masscon and masscon raw material cost. The peak temperature at bioconc low heat concrete was 63.5 °C within 29.5 hours after pouring. It has thermal different at 19.5 °C. The cost of material was US$ 54.6 per cubic meter.

The canal blocking system is commonly applied in to control water table in peatland recovery during prolonged dry weather in tropical peatland. The canal blocking is an effective strategy in preventing peat fire in many areas in Riau Province. Various local material such as earth, timber, sand, stone, rock, and concrete have been used in canal blocks. The concrete canal blocks are usually built at the river downstream and need to be stronger, durable and stable than other materials. Tropical peatland is a highly organic and highly acidic environment that could damage and reduce concrete structures service life in the long term. In this research, strength properties and porosity were evaluated to indicate the effectiveness of using pozzolanic material to increase resistance to the acid attack in concrete canal blocks. The concrete was produced by incorporating 10% Palm Oil Fuel Ash (OPC POFA) as a pozzolanic material from biomass to replace the Ordinary Portland Cement (OPC) cement content. The locally available commercial Portland Composite Cement (PCC) that contains pozzolanic material was also studied. The OPC concrete was used as a control mix with a target strength of 35 MPa. Specimens were cast and cured for 28 days in a laboratory water pond before subsequently placed in peat water canal nearby Rimbo Panjang Regency in Riau Province. The reduction rate in compressive strength, tensile strength, Young's Modulus of Elasticity, and porosity of concrete at 28, 91, 120 and 150 days were determined. Results show that the inclusion of pozzolanic material in concrete has increased the compressive strength, tensile strength, Young's Modulus of Elasticity and reduced the porosity. PCC and OPC POFA had better performance than the OPC concrete after immersed in the canal up to 150 days. Hence, it can be concluded that the pozzolanic material is effective in improving properties and acid resistance of concrete canal blocks in tropical peatland.

Waste tyres accumulate very quickly in a landfill as a result of the fast development of the transport industry, and mainly automobiles. The polymeric waste has limited usage and is rarely employed in a highly economic and viable product. A rigid pavement material needs to have high mechanical properties and durability when exposed to aggressive environments. In this research, a combination of waste tyre with rice husk ash and Portland Cement Composite (PCC) as a primary binder was designed to produce concrete that meets the requirements of flexural strength value of the rigid pavement based on the Indonesian Standard from Bina Marga 2018. Eight mixes with a variety of water/cement ratio (0.30-0.40), crumb rubber (2.5-7.5%), and rice husk ash (7.5-10%) were designed in this research. The control mix was PCC concrete. The crumb rubber substituted the fine aggregate content, while the rice husk ash replaced the cement content in concrete. The specimens were cast and subsequently cured in water pond up to 28 days. The mechanical properties of concrete, namely compressive strength and flexural strength were determined for all variations. Based on the results, Mix 1 with w/c ratio of 0.30, crumb rubber of 5%, and rice husk ash of 10%, performed both the highest compressive strength and flexural strength values of 36.38 MPa and 4.53 MPa, respectively, after 28 days. Both values fulfilled the requirements of the Indonesian Standard Bina Marga 2018. It can be concluded that an appropriate combination of crumb rubber and rice husk ash improves the mechanical properties of the concrete and has potential as a rigid pavement material.

Cantula Fiber (Roxb Agave Cantula) is a natural fiber that can be developed as a reinforcement material in concrete and can be applied to structural and nonstructural elements of a building. This research aimed to test the direct tensile strength of polymer modified mortar by strengthening cantula fiber in various forms of cantula fiber reinforcement ratios. Test specimens were in the form of polymer modified mortar with reinforced woven fiber and short fiber as textile reinforced concrete (TRC). Specimens used were in the form of plates measuring 12 mm x 80 mm x 400 mm with variations in fiber reinforcement ratios of 1.5%, 2.5%, 3.5%, and 4.5%. Test specimens were tested at age of 3 days and 28 days. The results of the test showed the highest increase in the reinforcement ratio of 4.5% in the PMM specimen with a tensile strength value of 2.41 MPa at 3 days and at 3.41 MPa at 28 days. Meanwhile, the value of the largest tensile strength in TRC was found on the reinforcement ratio of 3.5% with a tensile strength of 2.95 MPa at 3 days and 3.38 MPa at 28 days. Therefore, the effective reinforcement ratio ranged from 3.5% to 4.5%.

This paper presents the experimental study on the penetration of chloride ions in fly ash based-geopolymer concrete in the salt-water. To determine the corrosion possibility of reinforcement, lollipop-shape specimens with the size of 10x10x15 cm were prepared with the plain steel bar in the middle of concrete. The specimens were exposed to chloride ion penetration for 30-120 days. The mixtures were varied with alkali concentration of 8M-12M with the mass ratio of Na2SiO3 to NaOH was varied from 1.5 to 2.5. Specimens made with portland cement concrete was also prepared as the control. The best performance was showed by specimens made with 12M of NaOH. Due to ion exchange on the surface of geopolymer concrete, less chloride ion was found in geopolymer made with high alkali concentration. After 90 days, Portland cement concrete showed less performance while geopolymer concrete showed the strength increasing. High binding capacity due to soluble silicate content in geopolymer concrete was one of the reasons why geopolymer specimens are more resistant to chloride ion penetration.

Maintenance and rehabilitation as parts of pavement's life cycle become more important since it's an effort to restore the road condition as planned. This process will produce the emission of greenhouse gases that give an impact to the environment. The Live Cycle Assessment (LCA) was used to estimate the GHG's emissions. With LCA we could identify the unit process that will produce the GHG's emissions during maintenance and rehabilitation of road pavement. This research aimed to identify the unit processes of the maintenance and rehabilitation of rigid and flexible pavement and to analyse the amount of GHG emitted during this process. Four local roads in Indonesia were investigated as case studies. The result indicated the amount of energy of the unit processes as well as the GHG amount. This will lead to the identification of the hotspot of flexible and rigid pavement maintenance process. In rigid pavement maintenance activities, the hotspots included the asphalt transport process to asphalt mixing plant, cement transportation to the batching plant, and cement processing. Meanwhile, in flexible pavement maintenance activities, the hotspots were the asphalt transportation to asphalt mixing plant, transportation aggregate, and transportation to site.

Ground granulated blast-furnace slag (GGBS) is commonly used as partial cement replacement in concrete production. Although the use of GGBS has many advantages, it possesses a lower initial hydration rate that leads to lower early strength. Therefore, an attempt to use sodium silicate to activate the GGBS was carried out to promote the early strength of cement-GGBS blended paste. Based on experimental results, incorporation of 5 and 10% of sodium silicate slightly reduced the flowability and final setting time of blended paste. For hardened properties, the addition of sodium silicate reduced the strength at early age until 28 days. The modulus of elasticity of activated paste with sodium silicate was lower at early age, however at 28 days the result was comparable with the control specimen. The addition of sodium silicate decreased the ultrasonic pulse velocity (UPV) value at early age, however, at 28 days, 5% sodium silicate specimen had a higher UPV value than the control specimen. The different trend between UPV test and compressive strength test was suggested due to the inhomogeneous structure of activated blended paste that had a different mechanism during destructive test (compressive strength test) and non-destructive test (UPV test).

To achieve sustainable long-living infrastructures such as steel and composite bridges, the improvement of the fatigue behavior is crucial. By using high frequency mechanical impact (HFMI) treatment of critical welds, the fatigue service life of welded structures can significantly be extended due to the introduction of compressive residual stresses. Particularly with the use of high-strength steels in combination with HFMI-treatment has become economic in terms of fa­tigue design, thus, leading to reduced use of material resources. Even for welding in existing structures, positive results have already been achieved with post-weld treatment. For this inno­vative method, the amount of lifetime benefit and the conditions for successful application in the view of quality assurance have sometimes become object of critical questions. In various re­search projects, these questions could successfully be answered. By means of numerical and experimental investigations, design approaches have been developed and evaluated for the ap­plication of those treatments in constructional bridge design. The paper summarizes the results of two research projects on the subject of HFMI-treatment with the focus on the use for steel and composite bridges. An insight on the improved fatigue design, the practical use, the benefits for the constructions and possible application fields is given.

Due to the speed-up in processes of urbanization in developing countries large quantities of building materials are needed to construct the built environment. Mining activities to produce building materials lead to land-use conflicts, which negatively affect food security and degrade the environment, while consuming a large amount of energy. This leads us to an increasing recognition that resource efficient alternatives in building construction must be explored. However, fast growing cities in Countries like India are also frequently located in earthquake prone areas. Therefore, earthquake safety must always be taken into account when considering reduction of building material consumption. Simultaneously, thermal power stations produce a large volume of fly ash waste, which could be used to produce sustainable building materials as substitutes. Studies on the impact of building material substitution on reachable quantities of saved resources taking technical issues regarding the safety buildings into account are currently lacking. The contribution introduces a first case study on building material substitutes in different Indian buildings, comparing the bill of materials arising from the commonly built structure with ordinary brick masonry and potential material substitutes. The results show, that the use of alternate materials may results in a considerable amount of reduction in material.

In order to consider the environmental impact, this study investigated the effect of crumb rubber on the mechanical performance of cold mixture asphalt. Crumb rubber was obtained from the process of recycling waste tires, which this waste material becomes a major environmental problem due to the rapid increase in the number of motor vehicles in Indonesia. Cold mixture asphalt is an environmental friendly option on flexible pavement, which reduces energy consumption because it does not need heat during the process as in hot mixture asphalt. In this study, laboratory tests were conducted for Dense Graded Emulsion Mixture Type IV. The first stage in this study was to perform laboratory experiments on compacted mixture to determine the optimum residual bitumen content. In the next stage, a series of tests on crumb rubber mixtures were conducted in the optimum residual bitumen content condition to investigate the effect of crumb rubber as a partial replacement of fine aggregate. Fine aggregate in cold mixture asphalt was replaced with 50% of crumb rubber. Three different sizes of crumb rubber, 20 mesh (0.841 mm), 40 mesh (0.42 mm) and 60 mesh (0.25 mm), were applied in a series of laboratory experiments. Tests were done using Marshall Test equipment to obtain the mechanical performance of cold mixture asphalt. The finding indicated that finer crumb rubber produced higher stability than the larger size of crumb rubber. Even though the use of crumb rubber decreased stability of mixtures, it still met the minimum specified requirement of cold mixture asphalt. The stability of the crumb rubber cold mixtures were also comparable to hot mixture asphalt. Replacement of fine aggregate with crumb rubber on cold mixture asphalt is expected to overcome the environmental problems by reuse the waste materials to preserve the natural aggregates.

Geopolymer hybrid is a combination of geopolymer and Ordinary Portland Cement (OPC) or other binders to produce an alternative binder. This type of binder could be used to transform low-quality fly ash into multi-purpose concrete. Ordinary Portland Cement (OPC) concrete subjected to an acidic organic environment such as peatland, is more prone to deterioration in long-term than concrete using the supplementary cementitious material. In this research, the geopolymer was made by activating low-quality fly ash (contains more than 5% carbon) with the alkaline activator. The inclusion of OPC and Portland Cement Composite (PCC) as a fly ash replacement material is intended to promote curing at ambient temperature and immobilization of heavy metals in fly ash. The specimens were cast and cured at ambient temperature up to 28 days. OPC was used as a control mix. Subsequently, the concrete was immersed in fresh peat water in the laboratory up to 28 days. Characteristics of the geopolymer hybrid such as compressive strength, porosity, and leaching were determined. Microstructure analysis, such as SEM-EDX and FTIR, were conducted. Results show that the geopolymer hybrid has a good strength development at early days. At 28 days, there was a reduction of strength and increase of porosity, probably due to the attack of calcium from the OPC concrete. There was a transformation of aluminosilicate gel into C/N-A-S-H that is advantageous for the strength development at the early days. However, a weaker material has formed in the long term that cannot resist further acid attack. It can be concluded that the geopolymer hybrid is a promising binder, but it is essential to design the material appropriately to have better strength, durability and environmental properties in the long term.

For an optimized maintenance strategy, the early detection of track defects is necessary. Mounted sensors (e.g. acceleration sensors) on in-service trains are very suitable for track monitoring. With the continuous measurement of axle-box acceleration, short wavelength defects can be identified. For example, these defects can be rail breaks or cracks (i.e. rail defects), or local instabilities. Local instabilities can reduce the track quality in a short period of time. For an efficient data analysis of the acceleration signal and classification of different track defects, the development of appropriate methods is necessary. Therefore, a track-vehicle scale model was built to generate acceleration data used to detect typical types of failures. With the generated acceleration data, developed algorithms for pattern recognition can be easily tested. In the first part of this research, the vertical acceleration signals generated by the rail defects and local instabilities are collected, analysed, classified and prepared for being used in a model that can automatically identify these failures. The data is collected in a track-vehicle scale model, and after data analysis, the characteristics of the waveforms associated with each failure are examined using cross correlation. Every failure is classified both manually as well as automatically, and statistical features of the waveforms are extracted to create a database that is used to train a model using supervised learning. This model is described in the second part of the research.

For an optimized maintenance strategy, the early detection of track defects is necessary. Mounted sensors (e.g. acceleration sensors) on in-service trains are very suitable for track monitoring. With the continuous measurement of axle-box acceleration, short wavelength defects can be identified. For example, these defects can be rail breaks or cracks (i.e. rail defects), or local instabilities. Local instabilities can reduce the track quality in a short period of time. For an efficient data analysis of the acceleration signal and classification of different track defects, the development of appropriate methods is necessary. Therefore, a track-vehicle scale model was built to generate acceleration data for typical types of failures. With the generated dataset, developed algorithms for pattern recognition can be easily tested. In the second part of this research, three models created by the supervised learning method are trained and tested for the detection of the local instability in the vertical acceleration signal. The model A is trained with 78 laps and uses a manual classification. The chosen classifier for the model is a bagged tree algorithm implemented in the software MATLAB. The developed models distinguished between no failure, rail defect and local instability. For the training process of the model, the measured acceleration is treated statistically (e.g. Root-mean-square, Standard deviation, Spectral peaks and power). Subsequently test data for different scenarios is generated and used in the prediction model. With this model the track defects in the track-vehicle scale model are detected and classified very reliably. In contrast to existing methods, a machine learning approach is used for the non-destructive detection of the local instability. The results of the model are also improved by the model B and C by using 139 laps as training data, an automatic classification and an optimization of the statistics. The knowledge gained, can be used for acceleration data from in­service trains in regular operation, by adapting the developed model.

Prestressed concrete sleeper (PCS) is one of the important components for railway structural system. PCS sits on ballast (ground) and the load from the train wheel will be transferred through it thus distributed to the ground. In Malaysia, the ground condition from one place to another is unique. If the PCS sits on an uneven or unstable ground base, the load from the train may not be transferred smoothly to the ground and when that happened, the PCS might be damaged or broken into half. In this research, the researchers, with the help of the Keretapi Tanah Melayu Berhad (KTMB) personnel, studied about some problematic PCS that sit on an uneven ground base. By using the state-of-the-art on-site equipment, results were obtained and strengthened the KTMB assumption on their problematic sites. The data collection shows that the value of deflection is higher at KM20.75 compared to KM26.25 which is 18.90mm and 1.48mm respectively for 6-coach commuter and 8.45mm and 1.36mm respectively for Electric Train Service (ETS). This result may be affected by the existence void under the rail track structure at KM20.75 due to soil settlement caused by the underground water stream.

Green engineering can be applied to road infrastructure and in public transport. ICT application regarding bus operation can improve services to bus passengers. Furthermore, it encourages society to use public transport and it leads to sustainable transportation by reducing traffic congestion and pollution to the environment. The aims of this study are to evaluate the existing ICT application regarding bus operation, development of ICT application, and provide recommendations to improve services to the passenger. Case studies are ICT application in large cities in Indonesia i.e. Qlue in Jakarta, E-Wadul in Surabaya, and Pro-Denpasar in Denpasar. The results of cross-tabulation analysis indicated that implementation of ICT application on the bus is still at an early stage. Moreover, based on the level of importance and priority of passengers, the aspects of the application are response to passenger's report, bus services, and application facility to minimize reporting errors, whereas the aspects that have to be improved is the punctuality of bus' arrival at the bus stop and fixed bus schedule. Government and society have to work together continuously and consistently, so that ICT implementation towards green engineering could provide higher benefit to the passengers.

Yogyakarta is not only well-known as a student city in Indonesia, but it is also famous as a national and international tourist destination. These factors result in a significant increase in road use year-after-year. However, the road length could not keep up with this development. It should be noted that more than 75% of road users in this city consist of motorcyclists. To travel safely, one should have good awareness and follows the traffic signs. This study was conducted by distributing 190 questionnaires to common people; online-transportation drivers and students who drive motorcycles, the goal was to examine their understanding of the existing 32 traffic signs and to observe road users' awareness of their obedience of existing prohibition signs. The study results indicated that the average percentages of drivers who have the correct understanding of 32 traffic signs is 77.11%. Based on gender, the total understanding in male respondents was 76.25% and in female respondents was 79.72%. Despite of good understanding of the prohibition signs, there was 304 violations from the motorbike riders in one-hour observation.

Tanjung Priok is a port with a high level of import-export activity, and the flow of container movement is dominated by the Jakarta International Container Terminal and KOJA terminals. In addition to dwelling time problems, there are problems with the movement of the container trucks to and from both terminals, especially during peak hours of activity. The movement of trucks is dominated by single-move trucks (90–94% of the total movement of container trucks). An ineffective movement pattern can lead to a long queue that jams the existing road network around the port area. One solution to the problem is to develop an information system that can regulate the pattern of truck movements and adjust this to the level of service in the terminal and the ship docking schedule. A good distribution pattern will then optimize the movement of the trucks and reduce ineffective and inefficient movement.

There are many losses in nodes of the rubber supply chain. Rubbers are brought by boat to the Musi river estuary and sent to Mother Vessel near Singapore. If the nodes, where the rubber production is supposed to be collected, are not in function, then the rubber chain will be damaged. Farmers prefer to keep their rubber at home and wait for the middlemen to buy and collect them directly from their home. The productivity of rubber fell sharply as the price went down, and several big factories that have been shut down. This study aims to identify the characteristics of rubber trips, analyze the Nodes of the element of multimodal trips and multimodality per segment of rubber commodity trips, and make scenarios of improvement of the transport system for rubber in South Sumatera by means of information technology system. Transport data is analyzed by Matrices Analysis followed by VISUM program analysis. Interpretation of Land Image to recognize the area of rubber plantation is carried out using Image Landsat 8 and multispectral Analysis. The results will be the information system to improve hinterland productivity and multimodal rubber transportation.

Green Rating System is utilized as tools to analyze the sustainability of buildings or infrastructures. Improvising green rating system is a continuous effort due to the needs of local implementation of a country. In Malaysia, there are two established rating systems for roads; MyGHI for highways and pHJKR (Roads) for non-tolled roads. Preliminary study on pHJKR (Roads) identified this rating tool assess road sustainability performance only at planning, design & construction stages. This study foresees, it is essential to sustain its engineering and sustainability performance, including carbon assessment under Operation and Maintenance (O&M). Therefore, this paper highlights the relevance and applicability of pHJKR (Roads) in comparison to other establish green road rating tools. The assessment criteria and elements during (O&M) phase are proposed for score development, which extensive research will lead to the establishment of O&M pHJKR (Roads). The data was gathered and analysed from a comprehensive review of current pHJKR (Roads) with a comparison other green road rating index. The expert panel discussion also was utilized to determine suitable sustainability factors. This study, in conclusion providing an opportunity to the enhancement of pHJKR (Roads), which offer a complete cycle of assessment in road project development of road Green Rating System.

Resilient modulus (MR) is a property to measure the material's stiffness in designing asphalt pavement thickness. The value is usually calculated from an Indirect Tensile Test (ITT) for decades since it is considered efficient and more practical in most applications, and it only uses a single loading time and temperature. The Austroads 2008 still included the resilient modulus values from ITT as an input value at the initial pavement design stage due to its practicality in the application, although this conventional approach has no longer been used in a mechanistic-empirical design guide by NCHRP. In this research, three asphalt mixtures with variables of aggregates diameter and type of asphalt using Western Australia materials were investigated. The mixes, i.e. AC10-320, AC14-320, and AC20-320, were cast in cylinders with a dimension of 75×100mm at a reference temperature of 25°C. The indirect tensile strength used triplicate samples. Research shows the resilient modulus values increase with an increase of nominal maximum aggregate size and a decrease of air voids percentage. The highest MR values were given by mix AC-320 with 3% air voids compared to other mixtures variation. The reasons are an improvement in particle-to-particle contact between the aggregates and density with low air voids in the mixes. From this study, the resilient modulus values of Western Australian asphalt mixtures still meet the lower part of the range of the Austroads presumptive values and recommend as indicative values for design input in pavement thickness calculation.

Evaluation of pavement structure has to be carried out periodically to monitor the carrying capacity of the pavement to withstand against loads. The evaluation using backcalculation algorithm to determine layer moduli is the most ideal manner in revealing the residual capacity of the pavement. Due to limited human resources, some agencies in developing countries rely on the use of pavement functional conditions to predict roughly layer structural capacity, however, this leads to unsatisfactorily and inaccurate results. To overcome this, deflection bowl method can be proposed to estimate an indication of the structural capacity of the pavement. The study aimed to evaluate the suitability of the deflection bowl parameter to represent the structure. To do so, an examination of the similarities of the pattern of the deflection bowl parameters and elastic moduli of the pavement layers along selected road segments was conducted, and statistical analysis was presented to justify the results. The results showed that deflection bowl parameters have a strong relationship with the layered moduli. The overlay above the existing surface layer that may consist of more than 1 layer up to 205 mm or 8 in. thickness also can be represented by the maximum deflection parameter.

Indonesian Highway Capacity Manual or IHCM (1997) is a manual used to analyse performance of Indonesia's road network. It has been more than 20 years since the manual is firstly published, so that some parameters such as passenger car equivalent (pce) and base saturation flow (S₀) are no longer in accordance with actual conditions, which is indicated by significant differences between IHCM analysis results and empirical data. Several studies have been conducted in many cities and rural areas across Indonesia to explore pce, base saturation flow or other adjustment factors, in order to update IHCM, so in general, this manual will be more appropriate for current traffic conditions. This study is aimed at obtaining adjusted saturation flow from three signalized intersections in Semarang City, based on a comparison between predicted queue lengths and the empirical ones. Using the vehicle departure time slice data for green time, the pce and saturation flow was adjusted using regression method. Adjusted saturation flow at the observed intersection can be simplified in equation S = 506.48 We + 1857.9. Addition of variables still needs to be considered to gain a more general equation.

Many research on mechanistic testing have come to likely conclusion that different test setup results in different performance. The aim of this paper is to analyse the stiffness modulus resulting from three different test setups, namely; Monotonic Uniaxial Tension Test (MUTT), Monotonic Uniaxial Compression Test (MUCT), and Indirect Tensile Test (ITT). They are monotonic tests. This paper will elaborate if there is any significant difference among the result of the first three tests. Master curves of stiffness modulus as a function of strain rate at reference temperature of 15°C were developed. The results show that there is no significance difference between the modulus resulting from the three tests performed at high strain rates. It's also shown that at low strain rate, the elastic modulus resulting from compression tests is in between indirect and uniaxial tension test's elastic modulus.

This corrigendum corrects the following error. There was a missing reference in the reference list. This has been included as reference 18.

[18] Al-Swaidani A M, Hammoud I., al-Ghuraibi I and Mezyab A 2019 Nanocalcined clay and nanolime as stabilizing agents for expansive clayey soil: Some geotechnical properties Advances in Civil Engineering Materials 8(3) 327-345

[19] Gueddouda M K, Goual I, Lamara M and Mekarta B 2011 Chemical stabilization of expansive clays from Algeria Global J. of Researches in Engineering: J. General Engineering 11(5) 1-8 Reference 18 should have been referred to at the following points.

[20] Kariuki PC, Shephered K D and Van Der Meer F D 2006 Spectroscopy as a tool for studying swelling soils. In: alRawas AA, Goosen, MFA editors Expansive soils-recent advances in characterization and treatment 15-24 (London, UK: Taylor and Francis Group)

Table 1. The reference [18] should have been indicated in the caption

Figure 2(a), Figure 2(b) and Figure 2(c). The reference [18] should have been indicated.

Figure 7 the reference [18] should have been indicated.

The reference (Gueddouda et al.) numbered as 18 in the older copy was corrected to 19. See the selection of the reference list above.

Figure 8 should include a reference to [18].

Figure 9. The reference [18] should be indicated.

The reference (Kariuki et al.) numbered 19 in the older copy was corrected in this version to 20. See attached reference list above.

Table 4. The reference [18] should have been indicated

References list Reference [18] was added in this version. See above list.