Table of contents

PREFACE NCWE 2018

It is a great privilege for us to organise the 2nd National Colloquium on Wind and Earthquake Engineering (NCWE) in 2018 which was held in Swiss Garden, Kuantan, Malaysia from 17 until 18 August 2018.

Once again the NCWE in 2018 was successfully organized by the Faculty of Civil Engineering & Earth Resources (FKASA) of the Universiti Malaysia Pahang (UMP) with the support from the Disaster Research Nexus, School of Civil Engineering, Universiti Sains Malaysia (USM). NCWE'18 aims to provide a platform for discussing issues, challenges, opportunities and findings relating with the wind and earthquakes in the Asian region, with an overarching colloquium theme of "Disasters in Malaysia: Tomorrow is a Mystery".

This volume of proceedings from the colloquium provides an opportunity for readers to engage with a selection of refereed papers that were presented during the 2nd NCWE 2018. Divided into few sections, the papers published here were picked up on the multi disciplines including seismology, geodesy, geology, civil engineering and environment. The papers selected depended on the quality and the relevancy to the aim of colloquium and in the interest of participants in general.

There were also two key note lectures within the colloquium; Professor Dr. Yukio Tamura- a prominent professor at the Chongqing University, China, presented his lecture on the Mathematical Model for Understanding Phenomena: Physical View and Mind View, and the second keynote speaker is the well-known "Bapa Gempa" in Indonesia, Professor Ir. H. Sarwidi from the Islamic Univesity Indonesia, with a lecture on the Lesson to Learn from Recent Earthquakes.

The National Colloquium on Wind and Earthquake Engineering (NCWE) in 2018 also served as a forum to researchers and scholars from different disciplines that have an interest in natural disasters and geo-hazard mitigation to share and discuss their research activities. There were some 50 participants including students, engineers, researchers and academicians whom had many fruitful discussions and exchanges which contributed to the success of the colloquium. Finally on behalf of the organizing committee of NCWE 18, I would like to thank all the presenters and participants for their unduly support. This is something that we will strive to do again in the conferences that will follow next.

Chairman, NCWE 2018

Dr. Mohamad Idris Ali

List of Chairperson, Editorial boards and Technical Committees are available in this pdf.

All papers published in this volume of IOP Conference Series: Earth and Environmental Science 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.

This work presents a new approach for geological copper mining detection from synthetic aperture radar (SAR) data. In doing so, such an optimization algorithm of Particle Swarm is implemented with involving TanDEM -X satellite data. TanDEM-X with highresolution spotlight mode of 1 m resolution and X-band with HH polarization are used. The four-dimensional view is reconstructed based on 3-D data obtained from TanDEM -X satellite data and 4-D phase unwrapping algorithm. The Particle Swarm Optimization algorithm is used with a 4-D phase unwrapping algorithm. The study shows that the Particle Swarm Optimization algorithm is used to optimize the 4-D reconstruction of copper mineralization after 2000 iterations with RMSE of 0.23. In conclusion, the Particle Swarm Optimization can be used as an automatic tool to monitor the copper mineralization. Further, 4-D visualization using TanDEM-X satellite can be achieved by involving PSO in the 4-D phase unwrapping.

This Known as residual rock formed due to chemical weathering of igneous parent rock, Bauxite is naturally occurring mixture of minerals rich in hydrated aluminium oxides. The origin mineral and geochemistry involved in Kuantan Bauxite forming is however, rarely unveil, in which cause to lacking experience and knowledge in handling bauxite as it causes air and water pollution to surrounding environment and public health. Mineral composition in a bauxite formation is primarily significant to be characterised as to define its geotechnical engineering properties and to decide suitable mining methods prior mining works shall be executed. Hence, this review based on previous research aims to identify bauxite distribution in Kuantan, outline the predominantly mineral composition that can be found in Kuantan Bauxite genesis in order to verify geotechnical properties of Kuantan Bauxite as potential to civil engineering material industry. Several review of previous mineralogy and geochemistry studies, shows that XRD is the preferable method in verifying mineral content in Bauxite deposits around the world. It is also found that Kuantan Bauxite is after Basaltic parent rock. Minerals content of Kuantan Bauxite after Basaltic are found as gibbsite, hematite, goethite and quartz. Gibbsite is found as dominant mineral in Kuantan Bauxite. This review is significant for future research that related to Kuantan Bauxite civil engineering materials as it creates better understanding of Bauxite background as demanding potential earth resources for economic growth of Malaysia.

This paper presents a preliminary study of seismic risk assessment in Kertosari village, Kalibening Subdistrict, Banjarnegara District, after the earthquake incident on 18th April 2018. The study was based on Hazard US (HAZUS) with Damage Probability Matrix to estimate losses of damage state with model building type (Reinforced Concrete Moment Resisting Frames-Low Height (C1L), Reinforced Masonry Bearing Walls with Wood or Metal Deck Diaphragms-Low Height (RM1L) and Reinforced Masonry Bearing Walls with Precast Concrete Diaphragms (RM2L)). From the results, the probability calculation of damage in Kertosari Villages, moderate damaged category is the most. Other damage categories are slight, extensive, complete and none. Meanwhile, based on site preliminary survey and data from Banjarnegara Municipal Disaster Management Authority [1] which has updated on 20th April 2018 in Kertosari village, complete damaged category is the most. Therefore, it is necessary an expert's judgment to refine building type model and the criteria of damage state for compatible Indonesian building.

Wind Hazard such as a tornado outbreak may lead to a serious threat especially in damaging properties. Tornado is rarely reported in Malaysia which makes the early assumption of 2014 occurrence is due to the cumulonimbus cloud formation process which was further intensified by the wind factors of the monsoons season. This study attempted to determine the spatial correlation between strong winds occurrence in relation to the wind characteristics during the tornado outbreak in Pendang district of Kedah. The GIS process was performed to determine the most likely wind speed and wind direction on that particular date and place which will further enhance the understanding of such phenomena. This study which was carried out based on the data obtained from the Meteorological Department of Malaysia produced a significant discussion that must be considered in future research.

This investigation affords a novel work in four-dimensional (4-D) reconstruction of the Nepal Earthquake deformation the usage of interferometry synthetic aperture radar (InSAR). To this end, the established InSAR techniques are carried out to two repeat passes of Sentinel-1 an images data. Additional, the four-dimensional phase unwrapping is carried out the usage of Flynn's algorithm, four-dimensional best-path avoiding singularity loops (4- DBPASL) algorithm and Pareto ant colony algorithm. The results expose that the Pareto ant colony algorithm achieved precisely in contrast to Flynn's algorithm, four-dimensional best-path avoiding singularity loops (4-DBPASL) algorithm. In conclusion, assimilation of the Pareto ant colony algorithm with 4-DBPASL phase unwrapping produce precisely 4-D surface distortion owing to Nepal earthquake.

Fire represents one of the most severe environmental conditions experienced by the reinforced concrete (RC) structures. The aim of this study is to examine the behaviour of post-heated RC columns. There were two different geometries of RC columns were cast, i.e.: square and circular. Eight RC columns were heated at 600°C for two hours and tested under axial compression load. The main variables investigated were column's geometry and heating temperature. The test results showed that the mechanical properties i.e.: load carrying capacity, elastic stiffness and ductility of RC columns significantly affected by heating temperature. Column's geometry highly influenced the loss of water of post heated RC columns, however, less significant on the mechanical properties of post heated columns.

The evaluation of the pressure produced by blast load on the structure surface and selected location around with the aid of hydrocodes is studied in this paper. The existing knowledge of predicted blast pressure has been embraced in this paper for initial design in engineering application. The acquired blast parameters from numerical results are compared with blast test data and empirical methods. Besides the comparison, the effects of mesh distribution and air volume size on pressure are also studied. The numerical simulation initially conducted in 3D free air explosion and followed by the consideration of an obstruction structure on the blastwave propagation. The numerical peak incident overpressure indicated, the pressure of 0.51 MPa at 4.62 msec is approximates the overpressure recorded in the explosive test carried out at Fort Leonard Wood Army Base. It is revealed numerically, the overpressure at the bottom part on the wall surface experienced the higher overpressure.

Rural houses are classified as low rise and non-engineered building. These types of structures are at risk of getting damage during a windstorm event. Many studies have been conducted to investigate the air flow characteristic using CFD for structures located on flat terrain. However, wind that passes a ridge terrain has stronger wind speed and can be a potential hazard to rural houses located on top of it. This study investigates the air flow characteristics along the 2-D profile of a rural house model located on top of a ridge terrain considering the effect of varying the terrain height. Computational Fluid Dynamics method was used with the aid of ANSYS FLUENT software package. The results presented in this study are in term of pressure coefficient both with positive and negative values. The flow patterns over the models are observed using streamline. The result showed the ridge terrain height influenced the pressure coefficient and flow pattern. The highest suction was observed for the steepest ridge terrain due to the build-up in the local up-slope wind acceleration.

Throughout the years, economic and mortality losses suffered as a result of intensified disaster events have been on the upward trajectory. Holistic assessment of disaster risks from economic perspective however has been partial at best. Thus, this study aims to recognize disaster risk factors in respect to economic perspective considered as crucial by construction industry stakeholders in Kelantan from an actual flood disaster scenario. It is also intended to find common aspects that the major disaster risk factors pertaining to disaster risk management may share; and to evaluate the influences of disaster management cycle posed to respective risk factors from economic perspective cited by the stakeholders. Specifically, this paper presents evidence using a quantitative analysis for identifying and ranking the disaster risk factors from economic perspective in respect to disaster management cycle via a focus group discussion consisting of key stakeholders from the construction industry. The results reflect that, in overall, damages and losses are the most recognized risk factor with 42.97% reoccurrences and this type of risk factor was also the leading risk factor cited by the participants in three of the four disaster management cycle phases discussed. Categorization and ranking of the risk factors could allow formulation of a much comprehensive disaster risk management processes and policies especially in respect to economic perspective where most damages and losses usually occur. The outcome of this study provides a basis for responsible agencies in identifying the important risk factors from the economic perspective to be considered when planning for new development or recovering from disaster events. Overall, this paper contributes to the knowledge of economic elements of a disaster risk management cycle.

Elevated reinforced concrete water tanks are one of the most essential structure to major cities and also in rural areas before, during and after a disaster such earthquake. It is important to prevent elevated reinforced concrete water tank from collapse so the water supply can be maintained. One of the methods used to evaluate the seismic capacity of elevated reinforced concrete water tank is the pushover analysis. Pushover analysis is based on the assumption that structure oscillate predominantly in the first mode or in the lower modes of vibration during a seismic event. The objective of this project is to study the effect of column size on the seismic capacity of elevated reinforced concrete water tank. A total number of 10 models of elevated reinforced concrete water tanks consist of 4 storey and 7 storey has been used for this project. All models have been designed repeatedly to 5 different size of column for each storey, where the beam size is fixed for each model. All models have been designed based on BS8110 to represent the existing elevated reinforced concrete water tanks. Then the pushover analysis has been conducted on all models to study the seismic capacity of elevated reinforced concrete water tank. An adequate information on seismic demands imposed on the structural system and its components by the designed ground motion will be provided from the pushover analysis. Based on the pushover analysis conducted in this study, the elevated RC water tank with larger size of column tend to have higher value of force at yield limit state and ultimate limit state.

Porous asphalt is an open-graded aggregate mixed with polymer modified binder that contains relatively high air voids after compaction to allow for water infiltration. The performance of porous asphalt, particularly the strength and durability are highly influenced by compaction temperature. Higher compaction temperature may decrease the mixture air voids, thus failed to achieve required mixture densities and reduce its ability to perform as designed. Meanwhile, lower compaction temperature could potentially increase the viscosity of polymer modified asphalt and decrease the adhesion between aggregates, hence promoted stripping problem on pavement. Therefore, this study investigates the performance of porous asphalt compacted at various temperatures. The samples were prepared by using polymer modified asphalt PG76, granite aggregates and hydrated lime as mineral filler. The materials were mixed and compacted using gyratory compactor at different temperatures. The samples were then tested for volumetric properties, Abrasion loss, Resilient Modulus, Creep and Moisture Susceptibility. Based on the results, it can be concluded that compacting the porous asphalt at low temperature will reduce its performance.

Compaction temperature is an important parameter that determines the volumetric properties of the compacted asphalt pavement. Using an improper compaction temperature can cause problems on the dense-graded asphalt mixture performance. If the compaction temperature is less than the desirable temperature, it can potentially reduce the density and increase the air voids, thus reduce the pavement strength. This study investigates the effect of compaction temperature on the performance of dense-graded mixture. The samples were prepared by mixing 60/70 pen bitumen and granite aggregates using Marshall mix design method. The samples were compacted using Marshall compactor at various temperatures. The compacted samples were then evaluated for volumetric properties and tested for Marshall stability, resilient modulus and dynamic creep. Based on the results, it was found that the variation of the temperature affects the volumetric properties. On the other hand, the reduction in temperature reduces the stability, resilient modulus and creep performance.

Present research studies the effect of Processed Spent Bleaching Earth (PSBE) on the compressive strength of foamed concrete as partial replacement for cement. The mixture and specimen uses of PSBE replace cement in the proportions of 10, 20, 30 and 40 percent by weight of binder were prepared and tested. The effect of PSBE as partial cement replacement on compressive strength, flexural strength, workability, density, water absorption and carbon content of foamed concrete were reported. Results indicate that 30% PSBE significantly improved the compressive strength of foamed concrete and other properties also performed well which behaviours are comparable to normal concrete There are fewer Ca(OH)₂ crystals and more CSH produces in 30% PSBE through SEM analysis is represent for its superior.

Hydrologic simulation that engages incomputer models is the cutting edge to boost the understanding and provide further reliable outcomes in estimating flow rate. US Army Corps of Engineers has taken an initiative to develop a stable and dependent model, HEC-HMS that can be used for many hydrological simulations. The value of parameter needed for the simulation basically depends on the method chosen for loss, transform and base flow. In this study, the model parameters are changed and the model calibration had been performed separately for the three selected methods, the Soil Conservation Service Curve Number (SCS CN) loss method, the Constant Monthly base flow and the Clark Unit Hydrograph for transform method, to determine the most suitable simulation and to obtain the highest peak discharge for every sub-basin of the Kuantan River. Every flow simulated undergoes the validation and calibration process, with the Nash-Sutcliffe index used as a criterion to compare the outcomes between observed and simulated hydrographs. At the end of the study, it can be concluded that SCS Curve Number, Constant Monthly and Clark Unit Hydrograph is the best method for loss, base flow and transform method consecutively in estimating the flow rate in Kuantan River Basin.

A series of earthquakes such as Sumatra-Andaman earthquake on 26 December 2004, Nias earthquake on 28 March 2005, and Bengkulu earthquake on 12 December 2007 had influences to a series of subsequence local earthquake in Peninsular Malaysia. Recently, East Malaysia especially Sabah has become earthquake prone region due to local fault. Hence, Malaysia is not totally free from seismic activities. Therefore, in 2009 Malaysian Public Work Department had concluded that it was worthwhile to consider seismic design input in new building which are located in medium to high risk earthquake zone. The effect of seismic design implementation on cost of materials has become an interesting topic to discuss. This study presents the estimation of steel reinforcement required for six storey hospital building in Malaysia with seismic design consideration. Two parameters namely as reference peak ground acceleration and class of ductility has been considered as variable. The result shows that the total amount of steel reinforcement is increased from 6%, 116%, 257%, and 290% for peak ground acceleration equal to 0.04g, 0.08g, 0.12g, and 0.16g, respectively compared to the non-seismic design counterpart. Beside, total amount of steel reinforcement is increase around 6% and 145% for ductility class medium and ductility class low, respectively compared to its non-seismic design counterpart.

This study was carried out to evaluate the soil heavy metals pollution in Gebeng industrial area using reliable ecological risk indexes. The inductively coupled plasma-mass spectrometry was used to identify the concentration of selected heavy metals (As, Ba, Cd, Co, Cr, Cu, Ni, Mn, Pb, and Zn). Based on the results, the decreasing of heavy metals concentrations in the soil samples were in order as follows: Mn > Cu > Pb > As > Zn > Ba > Ni > Co > Cr > Cd. Ecological risk indexes (Geo-accumulation, Contamination Factor and Pollution Load Index) indicated that the industrial zone (IZ) was moderately to highly polluted by As, Cu, Pb, Co, Cd and Ni, whereas there was no toxic metals in the residential zone (RZ) and swampy area (SA).

In Malaysia, almost all houses in rural area are non-engineered structures. The roof of these houses is susceptible to failure and many types if roofing failure can be expected. This study examines the pull-out capacity of several simple connections meant for tying the timber purlin to rafter. The types of connections are single nail, double nail, nail plus metal strap and nail plus rope. The tests were conducted on timber type Damar Minyak (Araucariaceae), commonly used for the purlin and rafter assembly of rural houses. The wind load was applied in the form of pull-out force generated via in-house frame and Universal Testing Machine. The results from the pull-out force versus nail displacement exhibited unique features for each type of connection. In the case of a single nail connection, the graph showed two phases. When the single nail is combined with another nail or metal strap or rope, the responses exhibited in three distinct phases. The first phase for every type of connections showed linear relationship. The failure pattern for nail only (single and double) showed gentle degradation of the connection strength. However, for nail and metal strap connection, the strength degradation was abrupt due to the yielding of the metal strap. On the other hand, for nail and rope connection, the failure phase was cascaded due to the progressive snapping of the jute fibre. The highest the pull-out resistance based on the maximum pull-out force was shown by the nail and metal strap connection.

Tremendous damage during windstorm hit rural housing greatly impacted their roofing system in Northern Peninsular Malaysia. Disaster risk mitigation is crucial to overcome the recurrence of these damaging effect yet still unresolved and worsen by years. The pre-identified risk on wind disaster and role of wind codes were studied to minimize the deterioration impact on the property and life. Purposive sampling was adopted for the total number of 107 respondents participate in this survey. Selection of the experts was based on skills capacity, knowledge, and vulnerable experience due to their involvement in design, build, retrofit, and operate. Pre-identified risk perceptions among expert group was captured using five-point Likert Scale questionnaire survey. The descriptive statistics and index average analysis using SPSS was performed to figure out the importance level of risk identification and the most significant influence factor between the pre-identified risks. This paper aims to explore the wind disaster awareness and risk mitigation perception among the expert. This study acts as a starting point to reconcile on the mismatch expectation and understanding on wind disaster risk mitigation thus, lead to the reduction of disaster risks.

Floods is one of the most common natural disaster which causes heavy damage to properties and human well-being. Usually, the terrain characteristics and meteorological properties of the region were the main natural factors for this disaster. In this paper, Kelantan was selected as the case study for flood risk analysis in studying the flash flood occurrence in December 2014. Geographical Information System (GIS) analysis were used to evaluate the potential flood risk areas. Some of the causative factors for flooding in watershed are taken into account such as maximum rainfall per six (6) hours and terrain. At the end of the study, a map of flood risk areas was generated and validated.

The forensic engineering of a collapsed reinforced concrete fin wall structure is presented in this paper. The investigative process considers the assessment between the actual wind load conditions structure during the time of collapse against the actual structural capacity of the structure. Three design conditions are considered in this study; in-situ wind speed during the time of incident, wind speed used by the design consultant and wind speed recommended by Jabatan Meterologi Malaysia (JMM) in 1995, which was the time of design. The structure is both analyzed from a static analysis and dynamic time history analysis standpoint. It was found that the amplification factor due to the near resonance of wind energies between 0.25-0.30 Hz and the natural frequency of the structure, 0.27Hz. This resulted in a amplification of 1.8 over quasi-static loading conditions as governed by CP3 design code. It was further found that the dynamic wind loading imposed against the structure was 10% less from the actual capacity of the structure determined via nonlinear pushover analysis. This result is at best marginal considering the inelastic performance of the structure and the actual as-built condition of the structure; giving strong indication to the role of resonance in the collapse. The technical interpretation of the design codes leading to the responsibilities of the design consultant are not discussed in this paper.

This paper presents an analysis of irregular reinforced concrete buildings with respect to fundamental period of vibrations. During earthquake, reinforced concrete building with asymmetric building system experience extensive damage due to this torsional irregularity. Torsional irregularity of reinforced concrete buildings has been analysed with taking the strength and stiffness eccentricities as the main parameters of the rectangular in-plan building system. Displacement demand in reinforced concrete building has been determined in terms of fundamental period of vibrations and the behaviour of the building system was presented using the normalised displacement of buildings. The hypothetical model has been analysed has been set up using varies values of fundamental period of vibrations using Ruaumoko program and the lateral displacement of the building were extracted using Fortran program. The results indicated through the damage index showed that the fundamental period of vibration plays an important role in earthquake studies on reinforced concrete building since earthquake induced excessive displacement to the building system under the increment of the fundamental period of vibrations.

This paper presents the comparison of experimental and modelling of hysteresis loops for a corner beam-column joint under lateral cyclic loading. The beam-column joint is a sub-assemblage of a two-story precast school building. The modelled hysteresis loops were carried out using HYSTERES Program using IHYST 44 rule which is under the Ruamoko 2D folder. Modelling of hysteresis loop is one of the important processes in determining the right hysteresis model to be used in predicting the performance of the whole RC building under different level of earthquake excitations. The validation was made by determining the parameters required based on experimental loops and comparing the hysteresis loops and it response in terms of ductility, stiffness and equivalent viscous damping which obtained from both experimental and modelled hysteresis loops. It was found that the program was able to give a good agreement between them with percentage different between 2.68% and 28.49%.

Buildings subjected to torsional effect may result to the floors of the building not only translate laterally but also rotate vertically. Torsional effects may significantly modify the seismic response of buildings, and even cause severe damage or collapse of structures. The current practices in earthquake design is to apply single earthquake on structure during modelling and analysis. However, in real earthquake occurrence, the earthquakes normally occurred repeatedly after the first event. This phenomenon can affect the stiffness and strength of the structural system especially for repeated strong motions. With greater damage expected and lack of time, any rehabilitation action is impractical. Slab rotation, a major response parameter to represent the severity of the torsional response of eccentric systems, is considered. The centre of strength (CR) and centre of stiffness (CS), as two interdependent and important factors to the torsional response of buildings, are investigated via eighty positions of strength eccentricities (er) and stiffness eccentricities (es). Hence, this paper presents the torsional behaviour of a single storey, three-dimensional asymmetric building under the excitation of single and repeated strong ground motions. These motions are applied in the z-direction and analysed for elastic and inelastic conditions. The results are interpreted based on two position models. Position Model A concludes that the effectiveness of CS reduces gradually until CS ratio (es/bz) ≤0.2; thereafter effectiveness of CR increases to cause elastic slab rotation. With repeated ground motion, the magnitude of inelastic rotation is increased; however es/bz ≤0.2 is maintained showing effectiveness of stiffness eccentricity irrespective of nature of ground motion. Position Model B shows that slab rotation is affected by repeated ground motion. Elastic/inelastic analysis under repeated ground motion must be conducted in oppose to current practice, so that the designed structure can undertake the elastic/inelastic demand; especially for the lower CR ratio values.

The present research investigates the durability performance of foamed concrete with PSBE as partial cement replacement upon exposure to acidic environment. A basic control mix of foamed concrete (FC) cube was designed for density of 1600kg/m³ and 30% of PSBE by weight of cement namely as PFC were cast. Then all samples were subjected to water curing for 28 days before immersed in the hydrochloric solution with pH 2 for 1800 hour. The mass loss of the specimens was measured at every 100hr until the end of testing period. The findings show that specimens containing PSBE experienced lower percentage of mass loss as compared to control specimen. The use of PSBE assist in generation of larger amount of calcium silicate hydrate gel through pozzolanic reaction that consume calcium hydroxide, a byproduct of hydration process which is susceptible to chemical attack. Generally, integration of PSBE as partial cement replacement enhances the resistance of foamed concrete towards acid attack.

Carbon emissions became one of the most significant issues that affect the environment leading to climate change and other environment problems. Concrete productions depend on cement as a main element. The manufacturing of cements produces high CO₂ emission which is approximately 5-7% of total CO₂ emission on earth. This paper will investigate the possibility of reducing the cement amount in concrete productions by replacing it partly with waste materials in the mixing design while maintaining acceptable quality of concrete strength and quality. Fly ash (FA) and eggshells powder (ESP) are the waste materials that are used for this research. The combination of FA and ESP between 35-45% has been used to replacement cement in the mix design. The replacement of cement with FA and ESP was conducted according to weight instead of volume. From the experimental, it is observed that cement replacement with 35% of fly ash and eggshells improved the compression strength and durability of the concrete as compared to the conventional concrete. In conclusion, replacing 35% in total (FA+ESP) instead of cement is an acceptable amount that can reduce the use of ordinary cement in construction applications.

The quality of fired clay brick from different factory varies due to the different method of a manufacturing process. This research was design into three stages which are i) characteristic material study, where the material sources was from 3 states in Malaysia (Sidam Kiri Kedah, Serendah Selangor and Beruas Perak), ii) wall performance before retrofit and iii) damage wall performance after retrofitting process using CFRP. Based on the result obtained, the engineering properties of fired clay brick from Serendah Selangor shows the highest value of compressive strength as compared to brick from the other states. It has the higher flexural strength, low value of IRA, low value of water absorption, and low value of porosity. For the wall performance, the result show that the CFRP horizontal pattern for brickwall made from Serendah Selangor was better than oher types Beruas Perak and Sidam Kiri Kedah with percentage of increment 76%, 22% and 1.9% respectively, after being repair with CFRP. As for conclusion, the strength of brick wall can be improved significantly with the application of using CFRP strip in the research.

The production of sewage sludge waste from waste water treatment plant is increased every year as it is also only dumped in selected dumping area without maximize the utilization of the waste. As we are towards the process of developing our country, the demand of cement in construction industry was also increased. The problem stated has spark the idea of this research is to study the mechanical properties of the concrete that using different percentage of Microwaved Sewage Sludge Ash (MSSA) as partial cement replacement. Other objectives of this research are to determine the optimum percentage of the replacement of the MSSA in the concrete. Microwave heating method with two different temperature which are Medium and Medium High temperature were used to study the effect of different burning temperature of the Microwaved Sewage Sludge Ash (MSSA) to the concrete. The content percentage of MSSA used was tested with 0%, 5%, 10% and 15% respectively. The MSSA concrete undergo curing day for 3, 7 and 28days were then test with Compressive Strength test, Flexural Strength test and Ultrasonic Pulse Velocity (UPV) test. Based on the result, MSSA concrete with 5% replacement and heated with Medium High Temperature shows the best in result which is 44.52 MPa, with 1.25% higher in compressive strength compared to normal concrete. The Flexural Strength test shows that the 5% MSSA-Medium High temperature concrete is higher than normal concrete which is 7.79 MPa. It is also shown that UPV value for 5% MSSA-Medium High Temperature had lower value than control sample, 4.640 km/s at the age of 28days curing. As conclusion, concrete that contains 5% of MSSA replacement and burned with Medium High temperature show the best result among other sample.

This paper presents the mechanical properties of porous asphalt (PA) with nanosilica (NS) modified asphalt binder in terms of its Moisture Susceptibility. This test is essential to evaluate the performance of NS-PA towards the resistance of moisture induced damage. Moisture susceptibility can be defined as the loss durability, strength and stiffness of PA due to the existence of moisture, causing the adhesive loss of binder and aggregate. It is interesting to know that the existence of nanoparticle with different proportion can affect the moisture susceptibility behavior of NS-PA. Three different percentages of nanosilica were mixed with PEN 60-70 type of binder in this study. Then, all these blended modified binder were used to prepare PA Grading B specimens using Marshall Mix Design Method. Nanoparticle used in this study was Nanosilica with the average size of 10 to 15 nanometer. In addition, Moisture Susceptibility of NS-PA was evaluated using Indirect Tensile Strength Test, based on Modified Lottman Test. From the result, the maximum TSR value obtained at 2% NS-PA, which was 91%. Meanwhile, for conventional PA (0% NS), TSR value was only 74%. In accordance to AASTHOT283, TSR value should be equal or more than 80% to withstand moisture induced damage. However, for PA, 70% TSR value is consider acceptable due to porous nature of PA that permit water to flow inside the mix. From this result, it was concluded that the optimum amount of NS required for PA to withstand moisture induced damage was 2%. Thus, with proper NS concentration, the performance of PA with NS modified binder in terms of moisture susceptibility can be enhanced.

This paper intends to explore the application of the Reverse Multiple Input Multiple Output (R-MISO) technique in the system identification of nonlinear structural behaviour. This paper introduces two concepts in improving the identification estimates of multiple inputs and nonlinear systems, which is the conditioned spectral estimation technique and the inversion of the frequency response function formulas. In this paper, a linear equation of motion with a nonlinear Duffing oscillator is modelled and tested using this technique in order to model the typical nonlinear stiffness characteristics of materials and their design limit. The results indicate a good fit between the predicted physical parameters and the model properties. The nonlinearities were successfully isolated in a non-iterative procedure and the parameters were correctly identified. Multiple coherency was used as a tool to describe the various contributions of the inputs to the system outputs.

Most of the rural houses in Malaysia are classified as non-engineered building. These rural houses are characterized by having overhang roof and kitchen house. There have been many cases of such houses being damaged during thunderstorm events. This study investigates the changes in the air flow characteristics due to the presence of a kitchen house. The roof pitch of core house, overhang and gap height were maintained at 27°, 0.5 m and 0.5 m, respectively. Computational Fluid Dynamics (CFD) simulations based on Reynolds-averaged Navier-Stokes equations (RANS) was used together with turbulence model, RNG k-ε. The results showed that the presence of a kitchen house slightly increased the suction on the roof ridge but significantly changed the flow pattern in the windward direction.

Rural house classified as a low-rise non-engineered building and it is vulnerable to damages during a windstorm event. Many studies have proven that the roof of a low-rise house is especially susceptible to damage and this phenomenon worsens for the case of rural house. This paper aims to investigate the change in distribution of pressure coefficient and streamlines pattern surrounding an isolated rural house by varying the wind directions. The analysis was conducted using Computational Fluid Dynamics method embedded in ANSYS FLUENT software package. The results showed that in most cases, the roof ridge exhibited the highest suction. The maximum suction was observed for Model A2 (30° from the normal to the major face of the kitchen house).

This paper presents a numerical investigation on the impact resistance of reinforced concrete pier. The impact resistance of reinforced concrete pier was determined by simulating the impact from floating log onto a pier during flood, with and without scour. A single pier of 0.9 m diameter and height of 4.0 m was modelled based on the actual working drawing by Public Works Department of Malaysia. Concrete grade for pier varies from grade 30 to grade 150.The log impacting on pier resembles the impact load of 2.0 tonne as recommended in the design guideline. The numerical analysis is conducted with the aid of ANSYS Explicit Dynamics R14 software. Damage index was used to describe the fracture state of the pier. The flood velocity and impactor properties incorporated in the model were based on flood velocity studies and available hardwood in Malaysia. The results indicated that all the impacted pier exhibits local damage in the form of penetration and scabbing. The critical velocity for pier without scour ranges from 1.75m/s to 2.25m/s compared to from 1.75m/s to 3m/s with scour. The impact resistance of reinforced concrete pier is found to be insignificantly affected by pier concrete grade.

Aggregate is one of quarry product that is widely used in constructions industry. This raw material that produced from the fresh rock under the earth surface is the most important materials in construction that come from quarry. In order to obtain the quality material of quarry product the overburden material on the top of the fresh rock should be removed. However before going to this production stage the amount of the quality material should be determined. Overburden removal is very important to help the quarry operator to identify the only area that will be actively used for extraction. This paper presents the technique used in determining the thickness of the overburden for quarry prospecting using a geophysical method called as seismic refraction method. The non-destructive technique of seismic refraction was applied in producing the subsurface profile of the potential quarry area. Based on the seismic image the layer of bedrock and the thickness of overburden to be removed was determined. Result from borehole drilling also showed that the lithology of borelog data matched to the seismic result, to proved that seismic refraction can be used as a method in identifying the depth of bedrock.

The construction industry is one of the industries that currently gave an overwhelming effect to the booster of the developing country. Construction field is one of the areas that need immediate decision during the planning, design or construction stage. A construction project in a broader context is the involvement of multiple construction practitioners with an aim to ensure that the project complete within the time frame and budget with assured quality. In ensuring smoothness of the construction project, a multi-criteria decision making (MCDM) technique as a systematic tool has been used widely, namely Analytical Hierarchy Process (AHP). Based on the 40 journal articles, questions of which civil engineering field does AHP mostly employed as decision making tools in any of risk occurrence may be answered. Results revealed that thirteen (13) various civil engineering field was discovered adopting AHP as decision making assessment method and company and managerial, road highway project and building construction remarked the core field attracted much interest.

Peninsular Malaysia coastline is undergoing extreme level of erosion causing economic retardation and life threatening situation. National Coastal Erosion Studies 1984 shows that around 52% of Peninsular Malaysia's coastline is undergoing erosion and these value might have increased over the years. Hence, this paper aims to locate the erosion prone area in Peninsular Malaysia in response to monsoon by utilizing documented mass media reports. The review of mass media reports were analysed together with wind speed in representative of monsoon for the five years period to achieve the aim of this paper. The outcome of this study shows that the severity of coastal erosion in Peninsular Malaysia is increasing drastically. In addition, the northeast monsoon shows the highest impact on the erosion disaster especially in the East Coast of Peninsular Malaysia. The result from this empirical studies shows a good correlation between coastal erosion and monsoon in Peninsular Malaysia. Therefore, the coastal erosion is highly catalysed by monsoon (wind) as its prime catalyst.

The performance of porous asphalt (PA) mixture incorporating Nano kaolin clay (NKC) was presented in this study. The study covers basic properties of PA including morphology characteristic, penetration and softening point test. In addition, cantabro loss and resilient modulus test with regards to the variations of mix design of the PA was also examined. The kaolin clay used in this study has gone through the grinding process to produce the NKC with the percentage replacement of bitumen used was 3%, 5%, 7% and 9%. The results show that the used of NKC improved the physical properties of PA by reducing the penetration value, meanwhile increasing the softening point value. This indicates that NKC enhanced the temperature susceptibility of PA. The experimental result also show that NKC modified binder improved the durability and resistance to rutting and cracking of PA. Furthermore, 5% NKC is also considered as the optimum NKC proportion. The utilization of NKC is able to improve the physical and mechanical properties of PA. Therefore, it can conclude that the performance of PA is also enhanced with utilization of NKC in the bitumen.

The abundance of coconut shells (CS) have been involved in environmental issues. Yet new sources of aggregates should be found from environmental waste. CS and coconut fibres (CF) have been chosen from environmental waste to use in this study. Generally, this research concerns the partial replacement of coconut shells in coarse aggregates and coconut fibres as additives in porous asphalt mixture. CS and CF were put through chemical treatment by soaking in 5wt% of Sodium Hydroxide (NaOH) solution before being involved in the mixture. CS has been used to substitute 5mm of coarse aggregate with 0%, 5%, 10% and 15% while CF were added into porous asphalt mixtures with 0%, 0.3% and 0.5%. Permeability and air voids test were carried out to analyse the durability characteristics of porous asphalt mix. The results show that coconut shells and fibres can reduce the drainage time since coconut fibres in the samples could reduce clogging by binders. On the other hand, 15% of treated CS has a lower air void than untreated CS.

Porous cement concrete (PCC) is among the most effective voids reducer as compared to other types of concrete paver. The understanding on the techniques to produce durable pavement, the double-layer rubberized concrete paving blocks (DRCPB) was investigate in this study. Two rubber granules (RG) sizes, 1 mm to 4 mm, and 5 mm to 8 mm, were used as partial replacement aggregate to enhance the influence of DRCPB. The DRCPB containing 10 % (DRCPB-10), 20 % (DRCPB-20), 30 % (DRCPB-30), and 40 % (DRCPB-40) of RG designated with 10 mm, 20 mm, 30 mm, and 40 mm thick of top layer, and control concrete paving block (CCPB) were manufactured. Porosity and density test were carried out to analyse the durability characteristics of DRCPB. The results show that the porosity of DRCPB increased multiple when RG content increases from 0 to 40 % where the density of rubberized concrete is directly affected by the RG content.

Porous concrete is a concrete with continuous voids, which are purposely incorporated into concrete. The ability of the porous concrete pavement to allow water to percolate into the underlying strata depends on its porosity and permeability, which is one of its most important pore structure features. In this study, porous concrete pavement containing Nano from black rice hush ash (BRHA) was examined through the porosity and permeability test. A 66 nanometres size was used. Results showed that the porosity value of the specimens increases with increasing Nano BRHA content. In addition, the coefficient permeability of specimens was found to increase with Nano BRHA content increased. The results also indicated that the permeability coefficient has a strong correlation with porosity value.

This review focused on the identification of critical risk factors that influence the construction projects conducting in the developing countries. In order to attain this goal, a comprehensive literature review on risk management of the construction projects, particularly emphasizing on the developing countries was carried out. The identified risk factors can be a lead to achieve the goals of the project which includes time, cost and quality. This review used specific criteria to extract the risks factors based on the main purpose of the study. A sum total of 111 risk factors were figured out from the previous studies. Based on the criteria used for the classifications, 56 risk factors were observed as the most crucial risk factors influencing the construction projects of developing countries.

Waste cooking oil (WCO) is identified as a valuable potential waste material that can enhance the performance of conventional asphalt binder for road pavement construction. This study aims to evaluate the rutting resistance of bitumen incorporating untreated and treated WCO. Waste cooking oil dosage of 0%, 3%, 4%, and 5% by weight of binder was used throughout the experiments. The dynamic shear rheometer test was conducted to determine the performance of rutting resistance test. In addition, one way analysis of variance (ANOVA) was used to determined correlation of the sample. It was found that the rutting resistance performance was decreased as the test temperature increased. The results also indicated that modified binder with treated WCO exhibited the highest rutting resistance as compared to the untreated WCO. Based on analysis of variance it show that there are a significant difference in G*/sin δ for different untreated and treated WCO in modified binder.

In the shallow subsurface analysis, the potential hazard is identified and evaluated through the site investigation studies which can be determined either by conducting standard penetration test, cone penetration test, and multichannel analysis of surface wave (MASW). While the three methods stated are widely established and highly reliable, the result produced is sometimes unconvincing and lack of details. In this study, the horizontal to vertical spectral ratio (HVSR) analysis method is proposed instead of the more established methods. HVSR is a technique that based on the spectral analyses of recorded ambient noise in order to estimate the site effect parameters such as fundamental frequency and the amplification factor of local soil. The HVSR method was implemented in Bukit Tinggi, Pahang, Malaysia, which known to experience several small earthquakes between 2007 to 2009. Since the earthquake in central Peninsular Malaysia is uncommon, the tremor has caused panic and requires a thorough investigation of the soil effect in the region. The work conducted is motivated by this after effects with focus on the potential fault line investigation using the spectral ratio method (HVSR). The ambient noise signal measurements were performed at 20 sites along the probable fault line in order to calculate the HVSR. Receiver array arrangement and dimensions are chosen based on the prior information about the earthquake location as experienced by the local resident. At the end of the work, the amplification spectra for the soil column is evaluated at each site location, and the nominal frequency obtained, and maximum amplitudes are contoured showing the corresponding value trends in the region.

The influence of coconut shells (CS) and coconut fibres (CF) on the stability and rutting resistance of porous asphalt mixture is examined. Four different percentage replacement of CS and three different of CF as additives were investigate. CS and CF were put through chemical treatment by soaking them in 5wt% of Sodium Hydroxide (NaOH) solution before being involved in the mixture. Marshall Stability and asphalt pavement analyzer are performed to evaluate the Stability and rutting resistance of porous asphalt mixture. It was found that there appears to be an optimum CS replacement level of 10% and 0.3% CS during which the stability and rutting resistance increase significantly.

Asphalt durability is often linked to the thickness of the asphalt coating on the aggregate particles. In order to have an adequate film thickness in asphaltic concrete, there must be sufficient space between the aggregate particles in the compacted pavement. This void space is referred to as voids properties. Hence, this study investigates the performance of black rice husk ash as (BRHA) modified binder on stability and voids characteristics of hot mix asphalt. Four BRHA were used as in this study namely 0%, 2%, 4%, and 6% (by weight binder). The stability and voids properties of asphalt mixture were determined based on Marshall Mix design test. Test results show that the stability of hot mix asphalt incorporating BRHA was higher than the controlled mixture. The results also indicate that the addition of BRHA causes an increasing or decreasing in voids properties.

The recent JKR study for "Vulnerability Studies to Existing Building due to Seismic Activities in Sabah" had discovered considerable number of existing buildings suffer different levels of risk under seismic actions. Recognizing these existing building does inherit some design deficiencies in their earlier design stage, these deficiencies can be overcome either by enhancing the performance existing members or adding new structural elements to achieve the desired earthquake resistance level in terms of section capacity and interstorey drift. Few approaches outlined within the FEMA 547/2006 "Techniques for the Seismic Rehabilitation of Existing Buildings' had been used with this study in seek for most suitable retrofitting method in terms of performance, constructability and cost effectiveness. Three types of feasible retrofitting methods were covered within this paper, the performance comparison among retrofitting each method would be discussed as well. The evaluation criteria and upgrade schemes have been derived from analysis and assessment for this school facility building. The comparison for all the proposed methods of retrofitting an existing building can be measured in the terms of cost over average performance ratio. It can be concluded that each method is having specific advantages in the aspect of structural performance and cost-effective measures subjected to the characteristic of each studied approach.

This study had been carried out to identify sediment characteristics in Sungai Jemberau at Tasik Chini, and to compare their bed load dischargedata between the measured and predicted methods. It was observed that extensive uncontrolled mining activities nearby Sungai Jemberau had led to erosion and hence increasing bedload discharge. This situation hadbecome worst during storm or rainfall events because of increased sedimentation process.The river depth hadbecome shallow as the river bed was filled with bedload settles on the riverbed. Due to this situation, flooding becomes more severe as the river overflows. From here, the bedload discharge can be estimated using the DuBoys and Schoklitsch equation. Sediment size was classified using the Udden Wentworth Scale. Mostly, the median grain size (d₅₀) wasin a range of 2.0mm to 4.0mm, and was classified as Very Fine Gravel (VFG). Meanwhile, the density of sediment was in a range of 2.34g/cm³ to 2.97g/cm³. Lastly, the comparison between the measured and predicted bedload discharge shown that DuBoys equation gives better prediction of bedload discharge in Sungai Jemberau.

Construction management's knowledge is basis knowledge for one who works as civil engineer in construction industry. A good construction management will make the progressing of the project is more efficient and follow as in the plan also fulfill the customer needed as in the contract. The weak management will cause problem at site such as the delay, over budgeting and so on. As a civil engineer that involve direct with the site activities, they need to master this knowledge to manage the project. The purposes for this research are to identify and to determine the knowledge that a civil engineer in construction industry should have to be a competent engineer. The data collections are taken from the respondents who work as civil engineer with contractor class G6 and G7 in Penang state. The importance of this research is to determine the best knowledge characteristics that will be used for nowadays civil engineer. They will apply this knowledge during manage any project. The result from the survey will be compared with the data that get from the literature review. This is to identify the latest knowledge to be a guideline to become a competent engineer. From the result of the survey, mostly respondents who are civil engineers that involve in construction activities in Penang agree that have the knowledgeable in technical knowledge, decision making knowledge, teamwork knowledge planning and scheduling knowledge also leadership knowledge is very important to be a competent engineer.

One of the most significant regional earthquakes which brought catastrophic impacts is the magnitude of Mw = 9.1 earthquake which occurred on the western coast of Banda Aceh, North Sumatera had generated a massive Indian Ocean tsunami on December 26^th, 2004. Apart from that, several local earthquakes also occurred in Bukit Tinggi, Pahang and Ranau, Sabah according to Malaysian Meteorological Department (METMalaysia). However, oil and gas industry plays a vital role in Malaysian economy due to the significant contribution to the country's gross domestic product. In fact, the existing fixed offshore structure in Malaysia region only take into considerations the wind load, wave load, and current load rather than earthquake load. The objective of this study is to perform unity check for every element of offshore wellhead platform when subjected to 2004 Aceh earthquake loading. All the environmental loads such as wave, wind, and current load have been designed by referring the American Petroleum Institute (API) design criteria. The computer software SAP2000 is selected to model and analyse the offshore structure. There are three types of analysis that have been performed in this study which are the free vibration analysis, time history analysis, and response spectrum analysis. The time history of earthquake data from 2004 Aceh earthquake has been used in performing time history analysis. For the response spectrum analysis, the analysis was performed by using response spectra curves in Eurocode 8. As a result, the offshore wellhead platforms in Malaysia are situated under a safe condition when subjected to low seismic activity based on the study.

Pure bitumen production through crude oil petroleum refining process is not desirable in road pavement application. The asphalt binder exhibits insufficient properties for pavement construction and need to be modified with various additives. In this study, the effect of untreated and treated waste cooking oil (WCO) on voids properties of hot mix asphalt was evaluated. A 5% of WCO (by weight of binder) was selected and replaced into the modified binder before being mixed with the aggregates in asphalt mixture. The voids characteristic of hot mix asphalt was determined based on Marshall Mix design test. Five different content of bitumen i.e. 4%, 4.5%, 5%, 5.5% and 6% was chosen on the basis of min and max value as required by Malaysia public work department. Test results show that the voids filled with bitumen and density was increase as the bitumen content increases from 4% to 6% for untreated and treated WCO mixes. Furthermore, the result also indicates that the void in total mix was linearly decreased when the bitumen content increased from 4% to 6%.