Table of contents

FOREWORD

The International Scientific Conference CIBv represents one of the most important and traditionally scientific events of Civil Engineering and Building Services in Romania, enjoying increasingly higher visibility at the international level.

The aim of the CIBv conference is to provide a platform for researchers, engineers, academicians as well as professionals from all over the world to present their research results and development activities. It also provides opportunities for the participants to exchange new ideas and application experiences, to establish business or research relations and to find other partners and even friends for future collaboration.

The Conference has been organized each year at Transilvania University of Bra.ov, since 2000. In November 2019, Faculty of Civil Engineering was honoured to organize, in partnership with Shenyang Jianzhu University from China and to host the 14th edition of "International Scientific Conference – Civil Engineering and Building Services CIBv2019" in Brasov. More than 100 participants from China and Romania, as well as from Serbia, Croatia, Slovakia, Japan, Germany, Russia, Finland and Norway submitted over 80 papers to the scientific board which were presented during the conference. After a rigorous peer-review process (which included for each article at least two reviewers), 71 papers were finally accepted for publication in the CIBv2019 proceedings volume.

List of Honorary Committee, Organizing Committee and International Academic Scientific Committee are available in this 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.

In a society intensively urbanized, nature and green spaces have an extremely important and determined role. Solutions that are integrating different modern techniques related to a new or an existing building, with a tremendously positive effect over the natural building and horticultural sectors will represent an important factor in reducing the negative effect over the environment on a global scale. These smart solutions could extend the garden effect from the ground to the elevated levels of the building. Even if at the present moment there are different classic solutions to realize a green roof, in the last decades, have been developed different new and modern techniques for the greening environment. Taking into account all the above mentioned, the aim of the paper is to present the modern green roof systems considering all the changes that have occurred over time, and also to analyze a series of examples of how this concept has been adopted in different parts of the world and for varies structural systems. The authors consider that the study is very important in order to completely understand the characteristics of these systems and their main components, in order to properly design and implement them according to the present environmental needs. It is believed that the knowledge of this concept and its evolution and tendencies will help solve a series of ecological and social problems.

The emergence of new efficient materials, the high demands on the quality of the welded joints, while ensuring their safety in operation, outstanding aesthetic forms, the complexity of the new European welding standards, the pressure of the short execution times, had as result the adoption of modern solutions for steel and composite bridges. Durability is also one of the demands of the European Standards. The use of thick heavy plates can lead to reduction of the constructive depth, possibility for improved fatigue details, short execution time and easy maintenance. In this direction the fabrication efficiency is important, the need of a correct technology is vital. The role of the welding specialist is determinant. The paper presents some examples in the realization of modern steel and composite bridges with thick plates for the Romanian highways network.

The current state of testing methods for assessing the mechanical properties of old masonry buildings is reviewed, with a focus on the methods adapted for heritage structures. For these buildings, an accurate assessment is needed in order to minimise the interventions extent while ensuring an adequate structural safety level. As old masonries are non-homogenous and exhibit a highly anisotropic behaviour, numerous parameters are required for correctly simulating the behaviour under a given load scenario. In earthquake-prone areas, numerous failure patterns, in-plane and out-of-plane, can occur for the structural walls, each of them depending on different characteristics of the material. If for new masonries the testing procedures are standardised, for old buildings less standardised tests exist, while investigations are often based on modified or empiric methods. The testing methods can be classified as destructive, minor destructive and non-destructive. The destructive methods are the most precise but are extremely intrusive and may not be acceptable for heritage listed buildings. The non-destructive methods mostly provide qualitative results. The minor-destructive tests are often the most adapted for the study of historical buildings, as they can provide relevant information while affecting only in a limited extent the existing elements.

In this paper, the dimensioning of the load-bearing structures A, B and C of building complex in the surroundings of Salzburg, Austria is given. The floors of object A are underground floor, ground floor and two floors, and for objects B and C it is underground floor, ground floor, first floor and the attic. These buildings have an underground shared garage. The foundation is 30 cm thick reinforced concrete slab, with capitals 200/200 cm, thickness d_pp = 20 cm that are constructed in the middle part of the garage under the columns. Other underground parts of the buildings are the basements of each individual building. In addition to the common garage, the buildings have a common part of the ground floor, which connects the separate buildings. The construction of the garage at ground level is in the form of reinforced concrete slab with thickness d_p = 35 cm with reinforcement-capitals under the columns with thickness d_kpl. = 20 cm. The foundation and the ground floor slab are separated by an expansion joint in the axis 7. The waterproofing of the ground floor slab is achieved uniquely for the whole slab of the complex. Special attention is paid to the thermal calculation.

Energy consumption for space heating and air conditioning holds a significant share in the total energy consumption, among them residential and tertiary buildings being on the first places. This strong energetic dissipative character of different elements of the building envelope offers multiple possibilities of intervention aiming to reduce the heat losses. The Romanian requirements concerning the elements evaluating conformity with the Standard C107-2010 and the Order no.2641/2017 are given with a focus on thermal bridges influence aside with a short description of different ways to estimate this influence in EU countries. The paper presents in general, concepts to be used in order to achieve the nZEB standard developed by the Energy Performance of Building Directive having in mind a mitigation of greenhouse gases, GHG emission. In this context, is presented the role of balcony elements as undesirable "heat exchanger" and this thermal bridge is depicted together with some ways to avoid this inconvenience.

In this work the authors propose a parametric study for beams with the opening of 30 m and 60 m. The analysed structures are statically determined and the optimal height and the related weight were established based on strength and stability conditions of structure elements. The structure analysis was performed using a program developed in the Matlab environment based on the displacement method. The analysed beams are manufactured of S355 steel bars with annular section. The beams were analysed for loads applied both the upper and lower nodes of structures. Based on the obtained results a comparison was made concerning the efficient use of material used for the trusses in respect to their weight.

Drone technology has demonstrated to be of great contribution to the construction field. Tasks such as photogrammetry, plot surveillance and assets inspections are successfully automated with the aerial robotic technology with some level of contribution of a human operator. In this paper we analyse the possibility to achieve fully automated construction task using dispersed robotic system: a drone and mobile robotic crane. The role of the drone is to study the surroundings and generate a desired trajectory for the crane boom arm in order to lay-in pergola blades. The paper focuses on the layers of the dispersed cyber-physical system allowing to achieve such complex task and optimize the trajectory of the crane boom arm by resolving two-dimensional Chebyshev-Gauss collocation method in order to have minimum-jerk path.

In the last decades the landslide assessment plays a crucial role in land use development in order to minimize the negative effect of economic live and people's health. This paper present a GIS based landslide susceptibility assessment. This model is applied on the Littoral Coast line from Constanta to 2 Mai village, which is about 50 km along the Black Sea coast, crossing the Danube – Black Sea Channel at Agigea and passing through several resorts – Eforie Nord, Eforie Sud, Techirghiol, Costinesti and Mangalia. The data used are: geological map (lithology per geologic group), topographic maps of relevant scale to define slope angle (β), and some geotechnical parameters per geological group. For each of them a GIS map was produced. Based on the research results, we could conclude that Landslide Susceptibility Area (LSA) maps represent a great tool used in the identification of areas predisposed to landslides and could be used as support in the decision-maker process in order to propose environmental work protection or county planning.

Repair costs and downtime of a structure hit by an earthquake can be reduced, by implementing the concepts of removable dissipative members (bolted links which are intended to provide the energy dissipation capacity and to be easily replaceable) and re-centring capability (which is provided by the more flexible moment resisting frames) in a dual structure, obtained by combining steel eccentrically braced frames (EBFs) with removable bolted links, with moment resisting frames (MRFs). The seismic performance, re-centring capability and link replacement feasibility of a dual re-centring EBF with removable flush end-plate bolted links were already studied and experimentally validated. In this case, very short shear links were used in order to achieve the flush end-plate connection over-strength, so the connection can be kept elastic in order to make the link removal possible. Re-centring capability of EBFs with other types of removable links has not been yet approached. One of the main objectives of an ongoing research project is to extend the validation of re-centring capability and link replacement feasibility on extended end-plate bolted links. This type of connection geometry provides a larger connection capacity, thus shear links can be designed longer. The present paper numerically investigates the influence of using different link lengths (and connection detailing) on the recentring capability of two height levels structures.

The rural areas of Transylvania offer important resources for developing research in diversity of the cultural heritage. Many of these communities have seen great changes in demographics over the last 30-50 years, and important cultural heritage from previous generations is being lost in lack of understanding, human resources and willingness to preserve the value of our joint cultural heritage. The research seeks a digitisation approach to preserving and promoting the local cultural heritage, as well as a social science approach, which seeks to find answers to how one can be able to preserve, maintain and promote this cultural heritage, something which, according to the study hypothesis, can only be done if the communities see the benefits of doing so. The digital shift has the ability to create another level of understanding, opening a vast horizon for accessibility and progress linked with BIM technology. As an answer to dealing with the climate changes, degradation of the buildings due to natural disasters or more from the indifference of the young generations in regard of history inheritance, the study could be a valuable instrument in enhancing BIM-Heritage methodologies.

This paper aims to analyse the concept of water distribution system management and the modalities of including the optimization tools for increasing the process efficiency. Water distribution systems are often unable to respond quickly and efficiently to consumers demands. Water is a non-renewable resource and should therefore be treated with special interest. Sustainable development and optimization are the steps to take. A mathematical optimization model is presented in the second part of the paper with explanations regarding the steps followed. The result demonstrates the efficiency, speed and accessibility of using graphical-analytical optimization methods in the field of water distribution system.

This paper studied the behaviour of a medium height, confined masonry walls building, in a medium seismic area (0.25g, where g is the gravity acceleration), in Iasi, Romania. The study focuses on different masonry strengths impact on the building's elastic and plastic behaviour. It is important to establish if the structure can bare the gravitational and seismic loads if weaker bricks are used and also how the plastic mechanism is formed if the walls are made of stronger and stiffer masonry. It is also highlighted how the beams stiffness affects the structure ductility and how it can be improved. The building does not have the same stiffness on both X and Y directions, so this will also be taken into account.

The paper studies the influence of adding an aerated autoclaved concrete (AAC) masonry walls story above a reinforced concrete structure of a high building. This structure is situated in a high seismic area (0.30g, where g is the gravity acceleration) in Bucharest, Romania. The new story will be lightweight because of the AAC. It is necessary to establish if the existing structure can bare the new story gravity loads and to determine the new building's seismic behaviour. It is also determined if the new AAC masonry walls can bare the seismic loads they are to be subjected to. Both elastic and plastic analysis are present in the study.

Liquid storage tanks are special structures and strategically very important. In particular, water tanks are important to assure a continued operation of water distribution system in the event of unpredicted events. In order to ensure the operating conditions in normal parameters, the temperature of the stored liquid (drinking water) have to not exceed certain limits. The aim of this article is to investigate the most suitable thermal insulation system for a reinforced concrete overground water tank. In this regard, a comparative multicriteria analysis has been performed presenting the main advantages / disadvantages of each material (extruded polystyrene, basaltic mineral wool, organic ecological foam) taking into account several criteria. The scores obtained have been compared in order to highlight the most effective material in the case of the reinforced concrete water tanks.

The continued assurance of the needs of drinking water and the proper quality is vital for ensuring good living conditions. As a result of this idea, the risk analysis of the technological process of providing drinking water in the case of water tanks and the creation of a risk management plan and its permanent pursuit can lead to a more efficient process. Water tanks are high importance facilities for communities and during their lifecycle, there are a lot of uncertainties that can occur and affect it. In order to have an efficient and correct facility management during the functioning period, performing a risk analysis of these events is mandatory for this kind of constructions. Creating a good risk management plan and keep following it during the objective lifetime keeps the qualitative indicators of the water into planned parameters and the low costs.

The implementation of the image processing techniques for the analysis of the thermal field images captured with infrared scanners from the shield of the rotary kilns increase the quality of the information required for the optimization, monitoring and failure prevention of the kiln. In this work, authors presented a method that implement advanced algorithms such as the Radon transform, the segmentation and labeling of images for estimating the space-distributed, parametric model of the kiln's thermal field. The aim of the investigation is analyzing the similarities/differences between the thermal profile of the kiln and the kiln's maintenance events. The implementation of the proposed method proved that the correlations between the changes of the thermal profile and the renewal of the thermal coating of the kiln may be well emphasized. In this perspective, this method is suitable for building a thermal profile of the kiln during an entire maintenance time span.

The problem of determining the slope at a point on a map using level curves has practical applicability in designing the roads. This problem is reduced to the problem of finding the shortest length segment through a point that connects two coplanar lines. Two methods to solve this problem are presented: a fast approximate method and a slower but exact algorithmic method. The results are compared at the end.

For the concretes subjected to sulphate corrosion the use of the H II/A-S cement type is recommended. To improve the behaviour of these concretes to aggressive sulphate and magnesia corrosion, the use of the fly ash admixture collected by wet process for replacing the fine part of the aggregate is proposed. Because this type of corrosion is manifesting by expansion the analysis was conducted by measuring the dimensional modifications. In the Laboratory of the Faculty of Civil Engineering and Building Services of Iasi, an experimental program was conducted in order to assess the dimensional modification of the some samples prepared by concrete mixes based on belitic cements of type H II/A-S and embedding fly ash subjected to a combined sulphate and magnesia corrosion process using a mixed solution of Na₂SO₄ and MgSO₄ having certain concentrations. The prismatic concrete samples were preserved in distilled water and in the combined solution, and then after 28 and 90 days their dimensions were measured by the Graff device. In this paper is presented the behaviour of the concretes in the first life time and, as further research other samples will be tested for longer time.

Increased interest in wood as construction material has led to the development of research on improving physical and mechanical characteristics of different wood species or various types of processed wood. Since wood construction materials are combustible, it is necessary to improve their fire behavior. This is achieved by treating the surface or the mass of materials using flame retardant substances, which can delay the ignition and can reduce the speed of propagation of fire. Although its benefits: specific weight, thermal conductivity, chemical stability, good vibration and shock absorption, good dimensional stability against temperature, ease of processing, etc., wood has the great disadvantage that it will ignite easily, being a cellulosic material.

The aim of the study is to develop an experimental design of a complex air heater, conduct and analysis of the experiments, as well as to determine the main characteristics of the thermo-electric generator during the utilization of low-potential heat-La exhaust gases. The experimental setup consists of two units – thermoelectric generator operating on the principle of cross-heat exchanger heat exchange for heat recovery with parallel warmed of the supply air, which is supplied in the form of a mixture in the burner boiler unit and adsorber unit, filled blast furnace slag for the purification of waste gases from nitrogen oxides, c and carbon.

The aim of this study was to analyze the density, compressive strength, tensile strength and the freeze-thaw resistance of a cement micro concrete made with sunflower stalks that replaced 20%, 35%, 50%, 60%, 80% and 100% of the sand from its composition. The results showed, in general, a decrease of the analyzed properties, but the use of 20% and 35% sunflower stalk aggregates led to the improvement of the splitting tensile strength. A significant advantage of this type of micro concrete was its density, being obtained a lightweight building material, with up to 822 kg/m³.

The development of ultra-high strength and high performance concrete is a relatively new field in the profile industry. The last 150 years have shown that, despite getting more and more resistance, the practical applications have been too many times due to innovations in materials science. This phenomenon seems to be caused by the increased costs per unit of volume, as resistance increases, as well as a cautious retention of using new materials in practical applications. The present study aims to be an encouragement of practical structural applications by presenting an Ultra High Performance Concrete (UHPC), developed with locally available materials. As it is known, concrete is the main building material worldwide. In the last decades, his leadership position has been strengthened by the constant concern of the researchers and by obtaining the various types of concrete with increasing performances from the point of view of the fresh and hardened state, obtaining special structural applications.

Seismic risk is a measure of the damage that is expected in a specific area and time interval. It is based on the level of seismicity of locations (hazard), the resistance of buildings (vulnerability), and the type, quality and quantity of exposed assets (exposure). It can be measured by the expected economic loss, loss of life or damage to property size. Reducing the seismic risk comprises three phases: assessment, planning and implementation. The risk assessment requires a multidisciplinary approach that takes into account the expected physical damage (damage to buildings and economic losses), as well as social, organizational and institutional factors. At the city level, a risk assessment should start assessing the physical damage as a result of basic tools and the link between risk and vulnerability values of buildings. In this paper the creation of a database of existing buildings, classification of buildings and a procedure for determining the building typology that prevail in the city of Osijek is described. Based on the formed database, it is possible to implement certain seismic vulnerability methods.

This study is aimed to identify and to describe some of the most common types of pavement degradations that may develop on some Romanian county roads. According to the road safety management system, The County Direction of Road and Bridge Administration has the responsibility to ensure the traffic conditions, by preventing or repairing any degradation that may have adverse effects on the ride's safety and comfort. The most common types of degradations that can be identified on the Romanian county roads are: block cracks, longitudinal / transverse cracks, joint stepping, rocking, joint sealant defects and local declines. The process of interventions for restoring the road safety condition is continuous and span through the entire lifecycle of the structure (planning, design, build, operate, maintain and decommission). In order to illustrate the degradation state and to identify the most appropriate type of intervention required to restore the road safety condition, a case study is presented. The latter consists in a county road located in the Northern part of Romania (Suceava County), designated with the route number DJ 177A. The viability of the road was evaluated based on visual inspections and laboratory testing of its component materials. Based on the experimentally results several intervention works were suggested.

In this paper, the hierarchical regeneration mode of three-zone, four-zone and two-stage regeneration of the wheel is firstly determined. Silica gel is selected as the adsorbent, and toluene is selected as the VOC pollutant. Visual Basic software is used to establish the coupling adsorption model of heat, humidity and VOC pollutants in the staged-regeneration wheel. The dehumidification and VOC adsorption performance of the graded regenerated wheel with different influencing factors were compared, and the variation rules of the dehumidification and toluene adsorption concentration of the staged-regeneration wheel with different influencing factors were analyzed. The results show that, when the regeneration energy consumption of the runner is the same, the dehumidification capacity of the two-stage runner is the highest, the concentration of toluene adsorbed by the three-zone runner is the highest, and the dehumidification capacity and the concentration of pollutants adsorbed by the two-zone runner are the lowest. When the capacity of dehumidification is the same, the regeneration energy consumption of two-stage runner is the lowest, and the regeneration energy consumption of two-zone runner is the highest. With the increase of adsorption capacity, the lower the regeneration temperature is, the more significant the energy saving effect will be. When the capacity of dehumidification is the same, the concentration of pollutants adsorbed by the runner in the three regions is the highest. In addition, with the increase of air entrance temperature and humidity, the dehumidification capacity of the two-stage runner changes the most, and the adsorption concentration of toluene of the two-stage runner changes the most. When the concentration of toluene in the treatment zone was different, it had no effect on the dehumidification effect of the runner, and the concentration of toluene adsorbed by the runner in the third zone changed the most.

This article also put forward staged-regeneration wheel of the air conditioning system with condensing heat recovery technology, according to the climate zones in China, using the DesT software simulation in different areas of thermal and moisture load in a villa, and regeneration of the runner desiccant air conditioning system performance calculation, the results show that the compared with the two area runner desiccant air conditioning system, hierarchical regeneration runner desiccant air conditioning system performance are improved, the system of the refrigerant mass flow is reduced, the cooling load of the evaporator is reduced, the total load also significantly reduce energy consumption, air conditioning systems exergy efficiency improved; For regions with low temperature, low humidity or moderate humidity, the desiccant air conditioning system of three-areas graded regeneration wheel is more energy saving. In temperature and humidity relatively moderate areas, classification of renewable energy saving effect of the wheel were similar, but the four-areas wheel exergy efficiency obviously is higher than other wheel; For regions where both temperature and humidity are relatively high, the energy saving of the air conditioning system of the rotary wheel in the three-areas is not obvious, and the energy saving effect of the two-stage rotary wheel is the most significant.

The traditional flow meter is installed in the pipeline, not only to increase initial investment and cause stress loss to the system, but also to use a large amount of manpower and material resources in the data recording. In some areas that are not easily measured, such as buried in the ground, it can be difficult to measure. In order to solve these problems, based on the LabVIEW2013 as platforms and the hardware of sensor and data acquisition card, combined with the serial communication program to design the flow measurement system, getting traffic through the information collected data and the data acquisition card to convey in the program, get traffic after processing, according to flow to calculate the hydraulic balance, judging by the imbalance rate and the degree of hydraulic balance pipeline system is in a state of hydraulic balance. At last, through the actual test analysis, it is concluded that the flow measurement system for the conclusion of practical application, it not only can be used for pipe flow measurement and equilibrium state judgment, and also to have certain security on accuracy.

This paper presents a real example of optimizing the design of buildings and the systems they serve, through computer modeling and simulation. It highlights the capabilities of the DesignBuilder simulation software used as a design tool for buildings and systems for heating, ventilation and air conditioning. The paper also includes discussions and conclusions about how simulation results can provide important information for building design. The building for which the research presented here were done is the Transilvana University of Brasov Development Research Institute (Romania).

The article shows the need to improve repair technologies for bituminous pavements especially during the cold season. As a result of laboratory tests, it was found the need for other attempts. These are attempts on storable asphalt mixtures workability at various temperatures for the installation period, but also for the storage period. Through the laboratory tests was shown the complex interaction between mechanical behaviour of asphalt mixtures and variability factors acting on the road structure, this complex framework is determined by fundamental mechanical properties that influence long-term performance.

The bearing capacity and deformation performance of external T-stiffener box-column to I-beam space connections were analyzed in this paper. A great deal of full-path analysis of space connections has been carried out by using finite element program ABAQUS with different parameters, which are box-column section width, I-beam flange width, section height of I-beam, flange width and web length of T-stiffener. FEM is proposed for numerical simulation under cycling loading based on the mechanical properties of materials. The result show that the hysteresis curve is the spindle shape and relatively full of T-stiffener box-column I-beam space connections. The ductility coefficient μ is larger than 4.0 and equivalent viscous damping coefficient h_e is larger than 0.2 of the space connections, which have been met the limitation of the specification requirements. The bearing capacity and deformation performance of external T-stiffener box-column I-beam space connections can be improved with the increasing of T-stiffener flange width and web length effectively. Due to the fine performance of ductility, energy dissipation and seismic performance, the external T-stiffener box-column I-beam space connections can be proposed used in multi-layer steel structure engineering widely.

The fundamental vibration frequency and deflections due to the unit static force of the cross-laminated timber panels of different heights and spans were calculated. The calculation of the effective flexural rigidity was performed by the Gamma method. Obtained values are compared with the values obtained by modeling the construction in the Ansys software package. Three types of floor panels were analyzed with the same combinations of layer thicknesses in the cross section, but with different number of layers. The panels are 4, 5 and 6 meters long and 1 meter wide. Based on the results, recommendations have been made in accordance with current criteria that define the acceptable behavior of lightweight floor structures in relation to vibrations caused by human action.

The consolidation of wooden floors is a common intervention in the practice of building rehabilitation. The necessity of this type of works comes from the sensitivity of wood to biological degradation, the existence of a significant number of heritage buildings in which the construction of the slabs was done without ensuring compliance with the requirements of the normal exploitation (limiting the deformations), the occurrence in operation of the need to increase the capable loads. It is required, in case of consolidation at earthquake of the buildings with wooden floors, the creation of rigid slab (rigid in horizontal plane). The consolidation solutions that can be adopted are different, trying to respond to the diversity of situations/particularities which are encountered in practice. The paper briefly reviews the solutions currently used for the rehabilitation of wooden floors, then presenting a solution for the consolidation of a wooden floor belonging to an intermediate floor acted by gravitational actions, respectively a solution for achieving the rigid slab of an attic, of a multi-storey building.

Based on the engineering background of the deep foundation pit construction of Shenyang metro Line 10, the numerical simulation software Midas the GTS NX, and the three-dimensional integral calculation model considering the interaction of foundation pit supporting structure, surrounding soil and viaduct is established, and the numerical simulation value and the measured data are compared and analyzed, the applicability of the model is verified, the influence of foundation pit excavation on the deformation of pile foundation is studied, and the optimization scheme is given. The construction plan of Simulation + forecast is established to guide the practical construction of the project. The results show that when the depth of the pile foundation is 1.5 times the depth of the foundation pit, and the horizontal displacement of the pile foundation is within 1/2 of the control value, this is the optimal depth of the pile foundation. This is the minimum standard safe distance when the pier is 1/2 from the depth of the foundation pit.

Study on the tool wear of cutting white marble by multi-layer diamond coated tool, and discussion of the wear characteristics and failure mechanism of the tool are presented in this paper. Multi-layer diamond coating was prepared by hot filament chemical vapor deposition (HFCVD). It was deposited on the surface of cemented carbide ball-end milling tool. The surface appearance of the tool was analyzed by an optical microscope. The grain state was analyzed by scanning electron microscopy. Comparing the surface morphology of the cutting for 1h, the area where the coating peeled off became larger when the cutting tool was cut for 2 hours, and the falling range was expanded along the cutting-edge direction while the flank surface was expanded, and the tool joint wear was severe. The composition of diamond grains was investigated by Raman spectroscopy. Comparing the surface morphology of the cutting for 1h, the area where the coating peeled off became larger when the cutting tool was cut for 2 hours, and the falling range was expanded along the cutting-edge direction while the flank surface was expanded, and the tool joint wear was severe.

This paper presents the research, technologies and testing equipment developed for the energy plasma conversion of municipal waste in order to enhance energy-efficiency in the civil engineering domain. The purpose of this work is the environmentally friendly improving the efficiency of waste conversion processes by using controlled plasma decomposition reactors developed by the authors, which generate syngas, electrical and thermal energy which can be used in civil engineering.

A typical broiler house in the cold region of northern China was selected as the research object of this study. The environment of the broiler house was studied in depth by using the Airpak software. Then, an optimized design of air inlet devices for this typical broiler house in the cold region, under the condition of transverse ventilation, was made on basis of two influence factors: the length of the flow guiding device, and the direction of airflow. The optimized air inlet devices helped to improve the airflow in the broiler house, hence changing environmental factors such as internal temperature distribution, wind speed distribution, and carbon dioxide distribution. The length of the ideal flow guiding device should be approximately 1 m and not more than 2 m. Influence by the direction of the air inlet devices was affected by length of the guided airflow. Increase in the direction of the air inlet device led to rise of the body plane temperature of the chickens and the overall wind speed, while carbon dioxide distribution remained basically unchanged. The best direction of airflow (3) should be 30°∼45°.

The paper presents a combined method for the rehabilitation of a road on a restricted area by reinforced soil above a double sheet of piles. The principle is illustrated by a case study of a landslide in Bran, Brasov county. Due to the restriction imposed by the limit of properties we have to find out the way to stabilize a small part of the landslide and in the mean time to let the efforts induced by the rest of the sliding mass to act. To determine the status of efforts the problem on a restrained area without stabilizing the rest of the landslide which is much bigger we have considered that there are lateral surcharges due to the movement of the sliding mass.

The paper describes about solving the phenomenon of suffusion in the foundation ground of a building. The soil was investigated with direct and indirect methods (drilling and dynamic penetration, electric tomography, seismic refraction). The filling of the cavity was made with a low permeability or practically impermeable material, homogeneous in granularity, with approximately the same stiffness as the surrounding soil.

In the last decades, man-made environmental burdens have led to a significant increase of negative effects felt by the human race. Thus, some industrial sectors have developed and implemented a series of solutions with the goal of minimising their negative ecological impact. Taking into account that the construction sector is one of the most important economic players in every national economy, one that has a tremendous negative impact over the environment, in the last years, various recommendations and limitations have been drawn in order to reduce the consumption of non-renewable energy. In order to constantly reduce the impact of the built environment over the natural one, civil engineers should develop and promote sustainable solutions that have a direct effect on improving the environmental performances of the built environment. One such solution is the use of cold formed steel sections (CFS) for building new structures. This paper analyses the linear thermal transmittance of the thermal bridge formed by the vertical steel studs inside the external walls. The results show that these steel elements can be used in order to build energy efficient buildings.

Tuned mass dampers (TMDs) have been widely used for the control of seismic response of various new or existing buildings, successfully. However, the use of TMDs in the case of dual eccentrically braced steel frame structures has not been found in the technical literature. The paper appraises numerically the efficiency of TMDs in enhancing the seismic response of dual eccentrically braced steel frame structures and investigates the influence of mass of the TMD on the level of the response reduction achieved. To achieve these goals, a typical mid-rise five story steel frame structure with perimeter dual eccentrically braced frames, located in Bucharest, has been considered. Then, bidirectional TMDs with three mass ratios 0.04, 0.06 and 0.08 have been added on the top floor of the building, without redesign the frame members. Comparative nonlinear time history analyses of the unequipped and equipped structure have been performed with accelerograms of Vrancea 1977 type. Numerical results (peak base shears, peak inter-story drifts ratio and peak absolute story accelerations) show the efficiency of TMDs in mitigating the seismic response of dual eccentrically braced steel frames.

Optimization of civil engineering systems is a complex process that includes both theoretical and practical knowledge of experts from different disciplines. Optimization is defined as a rigorous process by which the methods corresponding to an engineering problem are analyzed and selected. The objective of this scientific paper is to define an optimal system / technique in monitoring the behaviour of civil engineering structures by topographic methods using the multi-criterial decision theory, by analyzing, combining and comparing some topographic methods and techniques used in monitoring the behavior of objectives by identifying decisional criteria (quantitative and qualitative) and applying one-or multi-criteria decisions. Finally, by choosing quantitative and qualitative criteria, we can establish the optimal techniques that correspond to the monitoring activity of the behaviour in service stage of civil engineering structures. The necessity for this optimal system that uses an algorithm is to reduce the risks and uncertainties that may arise from the monitoring process of buildings. Also, the results obtained must fulfil a certain accuracy, time and cost conditions, as well as their extent for other monitoring activities in topographical measurements.

Buckling restrained braced frames (BRBFs) are a relatively new structural system, characterized by high seismic energy dissipation. The Romanian seismic design code P100-1/2013 has recently introduced design provisions for buckling restrained braced frames. According to the code, the dissipative components are designed for the seismic forces reduced by behavior factor q, while the non-dissipative components are capacity-designed for seismic forces amplified with an over-strength factor Ω^T. The objective is to assess the code-based capacity design procedure using the nonlinear static analysis. Three structural configurations are considered: two BRBF configurations and a dual BRBF configuration. The structures are first designed following the code procedure, and then analyzed using a pushover analysis, using a numerical model of the buckling restrained braces calibrated on experimental data.

The aim of this study is to look at the level of knowledge about BIM (Building Information Modelling) in 3 important constructions sectors: higher education institutions (HEI) - companies – public bodies. In reference to the studies and surveys made in Romania by a team from Transilvania University of Brasov, in the frame of an Erasmus+ research project - UrbanBIM, it is reasonable to hypothesize that most of the people surveyed did not understand what BIM really is, and some were unable to identify the differences between BIM and CAD (Computer-aided design). Making population surveys and analysing the data allow for determining the methodologies for future implementation of BIM technologies and improving the educational training. The concept understating shows the preponderance of using BIM technology in the construction sector, developed on extended levels, starting from urban planning, geographic information system (GIS), architecture, engineering and construction (AEC), building management and leading to life cycle analysis (LCA) and energy efficiency (EE).

Riverbank erosion is a common problem of the Romanian freshwater system. Classic riverbank stabilization methods consisted of using different type of concrete, however concrete manufacture consumes large amount of non-renewable raw materials and energy, and it is a carbon-intensive process. Many efforts are, therefore, being undertaken towards the developing "greener" solutions. There are different type of retaining walls resulted from the need to avoid reinforced concrete wall solutions, such as gabion walls, solid masonry walls, rocky embankment prisms, and wooden pile retaining systems. But all of these solutions converge on gathering raw material from an external source, and transporting it on location. In Romania acquiring crushed stone tends to become problematic, especially, in the areas outside the Carpathian mountain range. Therefore a solution of using local soil as a base for a stabilized soil layer is very practical and economical from a technologic point of view. Being a hydrotechnical application, the freeze-thaw resistance of the stabilized layer is crucial for the lifetime of structures. The objective of our study was to determine this parameter, in accordance with the Romanian norms and regulations.

Development means a strong transportation network. Still, it comes associated with negative consequences, among them climate change and environmental disruptions. The pollution effects associated with road transportation are determined by a serial of factors like atmospheric conditions, topography, climate, traffic, fuel type, vehicle age but also improper maintenance of vehicles. All these components lead to atmospheric emissions caused by fuel leakage on rolling surface, dust and noise, accidental leakage of toxic chemical products. The present paper brings its contribution to the issue of sustainable development, approaching the problem of environmental impact associated with road traffic, quantifying pollutant emissions and comparing values. The evaluation is based on statistics for the most crowded road in Iasi City, namely Independence Boulevard, consisting of traffic data for the last 3 years obtained from the local Office of Traffic Management.

In modern seismic design, damping devices are used to increase the capacity of structures to dissipate energy. This paper evaluates the efficiency of using a passive friction damper system in a structure compared with typical structures and the influence of the damper's capacity on the structural response. The analysis concludes that dampers with lower capacity slip more times during earthquake than dampers with bigger capacity but the acceleration result increases.

The work is devoted to the study of the performance of reinforced concrete structures of engineering structures operating under the synergetic influence of aggressive environment with damage to concrete and main reinforcement.

With time a problem of preserving architectural heritage sites becomes more acute, since many unique listed buildings are in an emergency state and require the restoration measures that take into account the specifics of the historical environment, an analysis of the technical condition, evaluation of the monuments' value, the possibility of their functional adaptation to modern needs. The search for solution to preserve such objects is often complicated by the development of a modern urban renovation area around them and by the difficulties of maintaining a complete historical appearance of cities when adapting listed buildings to the functions demanded in modern society. The article proposes an approach to choose the best version of the project proposal for the restoration of a cultural heritage property of regional significance. The building is designed in an eclectic style in the city of Tambov. 11 versions of the author's project proposals for the restoration transformations are considered, which preserve the historical appearance of the building and various transformations of the internal volume and development options of the adjacent territory. 14 criteria are proposed to evaluate the qualities of versions. To select the best restoration version a scientific method of a multicriteria comparative analysis was used, which made it easy to compact a large amount of information about the object to a single quality parameter in the form of a synthetic indicator for each version. Simultaneously the weight factors of the criteria were established on the basis of expert evaluation obtained from the professional groups of various profiles: architects, representatives of the contractor, state supervisory authorities, the owner of the object, the tenant of the object.

This article discusses the change in the physical and mechanical characteristics of the foundation soil during the operation of construction projects and the possibility of taking these changes into account when designing shallow foundations. Methods Based on the assumption that the weight of the engineering and geological elements of the base remains constant regardless of the level of existing additional vertical stresses, an expression is obtained for determining the coefficient k_γ, taking into account changes in the density and specific gravity of the soil during the operation of buildings and structures. Moreover, based on the assumption that the plot of the additional vertical stresses is triangular, an equation for calculating the coefficient k_c is determined, which allows determining the change in soil adhesion during the operation of construction projects. Using the coefficients k_γ and k_c, an expression is obtained to determine the change in the calculated resistance of the soil of the base during the operation of construction projects. Taking into account the coefficient k_γ with the width of the projected foundation more than two meters with a ratio of settlement of the base to the depth of the compressible thickness equal to 0.3 leads to an increase in the design resistance of the operated base by 5%; by 3% and 1% with S/H_c = 0.2 and with S/H_c=0.1, respectively. In this case, depending on the width of the designed foundation, taking into account the coefficient k_c allows you to exceed R by 25%. Joint accounting of the considered coefficients leads to an increase in the calculated resistance of the soil of the base by an average of 27%. Conclusion The obtained coefficients, taking into account changes in the specific gravity and soil adhesion during the operation of the base, make it easy to estimate the growth of the design resistance during the compression process, which in turn makes it possible to save an average of 10% of the material when designing shallow foundations.

The article focuses on the satisfaction of the users/beneficiaries and on the quality level of the construction industry. Monitoring user satisfaction brings benefits in the construction industry by improving communication between the parties, engaging in mutual agreements, evaluating progress and monitoring the results and changes made. Users have certain claims about how they want to be treated, moreover, the physical product obtained must fit within their internal value system.

The article aims to show the construction on soft soil of a road embankment for access to a bridge which passes over a stream. To strengthen, consolidating and draining the embankment near the stream a combined geosynthetic and gabions solutions it was use.

The article aims to show the errors that a user can make in the use of inappropriate computing programs for the calculation of support structures and / or inadequate use of geotechnical data when designing support for deep excavations near roads in urban areas, and to indicate the software that offers plausible and reality-related results. Comparisons were made between the displacements and the efforts of ground support elements from numerical computational models in which was varied the coefficient of bedding for horizontal actions and between geotechnical calculation models.

The article describes the parallel operation of medium voltage (MV) transformers utilized in electric traction substations (ETS), their connection to the national power system (NPS), and the conditions required for the parallel operation of the ETS transformers. Solutions for the optimization of the parallel operation the MV transformers that power the electric railway traction system (ERTS) are discussed. In the case of multiple failure (fault transformers that serve a section) or load increase over the rated power provided by an electric traction substation (ETS), connection to the respective section of the adjacent ETS transformers is required. The parallel coupling of ETS is possible if High Power Transformers ERTS meet all the conditions for parallel operation. This mode of operation ensures the stability of the electricity distribution system for the consumer. SCADA systems can be used for monitoring critical situations and general optimization of electrical power supply of the railway electric traction system.

There are numerous cases when fires in power plant turbine halls causes the collapse of roof metal structures. The use of conventional firefighting equipment in high-bay facilities has proved to be ineffective or unacceptable. In this situation fire robots are the most feasible option. Today the best variant is a fire robot that is based on a traditional fire monitor and equipped with infrared fire seat detectors. Some specific advantages of fire robots include their ability to operate under low visibility with high smoke generation conditions that are typical of a fire in a turbine hall. The program of roof structures cooling down is designed and tested in advance so that fire robots can perform their functions in automatic mode. Fire robots can be included into permanent-type fire safety systems that are designed taking into account specific construction features of a facility and temperature conditions in case of a fire. Such composite system is a multifunctional complex that is able to perform versatile fire protection functions. The most appropriate fire robot types to be used in such complex fire protection system are fire robots based on conventional fire monitors, as they have some notable advantages compared with mobile robots or androids. One of them is their ability to protect big areas starting from 5 and up to 15 thousand square meters with fire suppressing media flow rate range just 20-60 l/sec correspondingly. Water or foam can be delivered via air exactly to the fire seat instead of spraying over the total designed area. Moreover, wetting intensity can be maintained at a level that corresponds to fire seat intensity.

This study is part of a larger research project, which looks at how modern hospitals are built in Norway, and what can be done to make hospitals more user friendly and purpose built. It looks at how medical facilities can be made to encourage a quicker improvement in the patient's recovery, and what effect the way modern hospitals are being built and operated, has on the patients, the employees and to the visitors to the health facilities. A key focus of the research is to look at nosocomial infections (hospital-acquired infections) from medical care and to study the prevalence of antibiotic resistance at these facilities. The project aims to find conclusions and areas of improvement along larger parts of the hospital and patient chain. The greater research project aims to look at this scientific field through studies in 3 countries, in Northern Europe, Eastern Europe and Central Europe, to get an idea of the inter-European challenges in a very complicated scientific field, with different financial resources, cultures, focuses, and approaches to the frequency of use of antibiotics.

The tendency nowadays is to reduce the consumption of conventional energy and to efficiently use renewable energy resources. Thus, the energy independence of the different consumers is tried, along which is the street lighting. There are many applications where street lighting is powered by renewable energy, using photovoltaic panels. This article presents a different solution for powering street lighting, with the help of wind energy, through Savonius turbines. A Savonius wind turbine with the overlap ratio of blades of 0.35 is tested, in order to determine its actual power coefficient and power extracted from the wind. According to the tests, a power coefficient of 0.3 was obtained for wind speeds of 4 and 5 m/s and the maximum power at a wind speed of 7 m/s. With the values obtained, for this type of turbine, different configurations of Savonius turbines have been dimensioned to supply an energy-efficient street lighting pole.

This paper presents a numerical study on the effect of confining pressure (down-to-hole pressure) on the performance of the thermal jet drilling on rock. For this end, a numerical method including a viscoplastic-damage model for rock and an explicit scheme for solving the governing thermo-mechanical problem, which is assumed uncoupled. Moreover, rock heterogeneity, which facilitates the thermal spallation phenomenon, is taken into account. Numerical simulations under axisymmetric conditions demonstrate that the efficiency of thermal spallation based drilling is reduces drastically due to confinement.

The purpose of this paper is to verify the validity of concrete strength monitoring method based on piezoelectric wave dynamic technology by the numerical simulation ways. Since the elastic modulus of concrete increases linearly with its strength, the elastic modulus of concrete at different ages is set to simulate its strength growth. The stress wave is transmitted and received by the piezoelectric sensor embedded in concrete, and the stress wave energy value is taken as the strength identification parameter, and its variation trend with the strength is analyzed. The results show that with the increase of concrete strength, the energy value of monitoring signal has a monotonically decreasing trend. In the early stage of concrete, the monitoring signal energy decreases at a large rate and then tends to be flat. In the early stage, the strength growth rate of concrete is faster, and tends to be flat in the later stage. Furthermore, the curve of capability ratio and strength ratio was established, and the two presented good linear lines. The results of this paper show that the concrete strength monitoring method based on pressure wave dynamic technology can be used to monitor the concrete strength.

The constructions with fluid retention and storage in general, between which the water holds a significant weight, are permanently exposed of physical and mechanical actions of deposited agent, with the continuous manifestation of the exfiltration tendency, herby the requirement of performance at tightness becomes essential. If the constructions that fulfill this role are realized of reinforced concrete, the tightness at fluid in general and at water in particular of the elements which compose the storage space is insured in a significant proportion by the waterproofing qualities of the structural concrete put in place. When the process of waterproofing concrete is clean and environmentally friendly and leads to improvement of initial physical-mechanical characteristics, represents an essential element in the combined approach of the performance requirements regarding the tightness and resistance condition. In this paper is presented a research study concerning the positive influence of waterproofing additive "Penetron" introduced into the fresh concrete mass used to realization of structural elements, with the role of storage and treatment of waste water, to mechanical characteristics of concrete after hardening.

In most situations, in the case of metal structures, the loss of stability occurs before plastic elements enter the structure. The present paper aims to compare the response of a metallic structure obtained by an elastic analysis of the 2nd order developed with the two methods provided in SR-EN 1993-1-1:1) global analysis that takes full account of geometrical and material imperfections and second-order effects; 2)-individual stability check of the equivalent bars using buckling lengths corresponding to the overall instability mode. Obviously the first method is the most complex because it takes into account both global and local imperfections. The second method is the simplest and most used method. In this case, the verification relationships take account of the imperfections of the elements. For global analysis, the global imperfections and local bar imperfections will be considered. These imperfections will be taken into account in the worst form and sense. The check for global analysis will be done using finite element meshing, while using the geometric nonlinearity option so that the stiffness matrix is calculated at each loading step. The individual check of the elements shall be performed according to SR EN1993-1-1 according to the type of request.

Interaction system vehicle-pavement represents actual problem in terms of structural, life service and environmental requirements. Experimental measurements with real vehicles and pavements are time consuming and bring high complexity of the inputs, relations and other boundary conditions which need to be identified to achieve reliable outputs. Inevitable uncertainties related to the real structure can be controlled when scale models with identified boundary conditions are prepared. Determination of the characteristics of the individual components of the vehicle-pavement interaction system at controlled conditions is then possible. The subgrade is an important part of the pavement structure. A laboratory and numerical simulations based on the static and dynamic testing methods were used to determine the deformation parameters of the subgrade. A viscoelastic mass was selected as a subgrade for the small scale model of the pavement. Its characteristic allows the simulation of the dynamic effects of the vehicle on pavement structure. A short-time dynamic loading of the subgrade occurs when the vehicle moves on the pavement. Therefore, the response of the subgrade should be also characterized with the dynamic parameters. The results obtained by the experimental observations in-lab will be used for the evaluation of the traffic effect on the pavement structure and surrounding objects such as buildings.

Building structures have been designed for more than 40 years to protect life in the event of a major seismic event. In order to achieve this goal with a minimal initial investment, structures are designed, using the ductility principle, as sacrificial systems, undergoing significant plastic deformations in the main structural elements, which progressively deteriorate. If in the design codes the structural damage is to some extent explicitly accepted and quantifiable, problems related to non-structural damage are addressed much more vaguely. This no longer meets market and society requirements. New structural systems are needed, which are not only efficient in reducing structural and non-structural damage, but also offer good re-centring capability, durability, reparability and affordability, accompanied by accessible design methods. This paper reviews the principal solutions that can be used to achieve these goals. Their advantages and limitations are analysed, as well as their potential as damage tolerant structural systems.

China envisages building a new undersea tunnel called Bohai Strait Tunnel to connect Dalian to Yantai, for the purpose of solving the detour problem in transportation. This paper analyses the passenger traffic in Bohai Strait Tunnel. A modified negative exponent network flow assignment model and an increasing rate method are used to predict the network flow assignment and passenger traffic volume after the completion of Bohai Strait Tunnel in 2050. Two formulas of economic benefits are employed to evaluate the effect of undersea tunnel on passenger traffic. The result indicates that the new undersea tunnel can shorten the distance, reduce the transport cost, save travel time, and produce good economic benefits. Tunnel transportation will attract a large number of passengers and become main transportation way. The analysis result can provide technical storage and references for the future undersea tunnel construction.

Recent years, more and more utility tunnels are adopted in China with the development of urbanization. Compared to the conventional method for utility installation, the utility tunnel that co-locates more than one utility underground eliminates the need for frequent excavation and reinstatement of roads. Ventilation systems are essential in utility tunnel for safety reasons, especially for gas compartments. This paper aims to evaluate effect of the longitudinal ventilation on gas temperature field by investigating the heat transfer process on gas pipeline. Numerical models including convection, conduction and radiation were established and then used to simulate the heat transfer process on gas pipeline. Results show that the ventilation has a great impact on gas temperature. In case of low inlet air temperature, the gas temperature may drop below -10 °C, which is too low to guarantee a normal operation.

Abaqus is often used to analyze the dynamic elasto-plastic response of tall buildings under strong earthquake. However, the analysis results of the hysteretic behavior of RC shear wall are not very satisfactory. In this paper, the residual strain is proposed to determine the damage parameters in the concrete damaged plasticity model in Abaqus, which include the damage factor and compression stiffness recovery factor. The method can greatly reduce the lagging or exceeding of strain in the compression reloading path. The confinement effect of distributed bars on concrete of RC shear walls is also considered. In addition, a secondary-developed uniaxial constitutive model of steel is adopted to present the Baushinger effect under the reciprocating loading. Simulation results are in good agreement with the test results. It shows that the methods purposed in this paper can effectively realize the simulation of the hysteretic behavior of RC shear wall under the low cyclic reciprocating loading.

In the modern processing technology, the machine tool plays an irreplaceable role as the main processing tool, and its machining accuracy directly affects the processing quality of the part. Because the spindle vibration caused by the rotor mass imbalance will seriously affect the machining accuracy of the machine tool, it is necessary to dynamically balance the spindle. The key step of dynamic balancing is to accurately extract the characteristics of the vibration signal, the phase of the vibration signal of the spindle was extracted by the all phase fast Fourier transform, the amplitude of vibration signal was extracted by cross correlation analysis, the results are applied to the influence coefficient method to realize the dynamic balance of spindle vibration The results show that the vibration signal feature extraction method combined with the results of the two extraction methods has high precision and stability.

The performance of the catalyst in the multiphase Fenton system is particularly important. It will directly affect the rate of hydroxyl radical generation during the multiphase Fenton reaction which is the main material for oxidative degradation of organic matter in wastewater. Therefore, it is necessary to select a suitable catalyst to construct a multiphase Fenton system. In this study, the preparation of CuO/CeO₂ catalyst in multiphase Fenton technology was discussed. The effects of CuO loading, calcination time and calcination temperature on CuO/CeO₂ were investigated. The best preparation conditions for the catalytic performance of the catalyst were as follows: the loading of CuO was 7%, the calcination time was 3h and the calcination temperature was 400°C. The catalyst prepared under this condition can achieve a COD_Cr removal rate of 34% for a plurality of Fenton processes.

In this paper, the static loading test of two assembled monolithic reverse-rib slabs is carried out, and the cracking process, mechanical mechanism and performance under different load combinations are emphatically studied. The test results show that the development of cracks of the assembled monolithic reverse-rib slab is fitted with the characteristics of the two-way plate. The rib beam and the floor slab between the rib beams can work well together, which can meet the requirements of normal use limit and bearing capacity limit.

The paper is focused on the mechanical properties of precast concrete frame beams with large-diameter and high-strength steel bars. The full-scale static tests and nonlinear finite element analysis were carried out on the two proposed beams with steel bars of HRB500 Ø32-Ø25 and Ø40-Ø32 to study the load-carrying capacity, flexural capacity and plastic rotational capacity. The influence of steel bar diameter on mechanical properties were explored. On the basis of equal-strength principle of flexural capacity at the same time, the finite element model of the cast-in-place concrete frame beam with large-diameter of HRB500 and ordinary steel bars of HRB400 were compared. Results indicated the properties of the precast concrete frame beams with large-diameter and high-strength steel bar. The load-carrying capacity of the prefabricated concrete beam with steel bars of Ø40-Ø32 was higher. The coefficient of plastic rotational capacity was 3.41 and 2.88 of specimens with steel bars of HRB500 Ø32-Ø25 and Ø40-Ø32, respectively. The positive section yield bending moment could be calculated by the current concrete codes. The properties such as yield load, flexural bearing capacity and the plastic rotational capacity were similar to the cast-in-place concrete frame beam, and could be verified by the current standard.

This paper develops a new analysis method to weaken bending moment at the end of support beam of the inner climbing tower crane. Firstly, the equivalent length of the variable cross-section beam is calculated according to the principle which the angular displacement of the variable cross-section beam is equal to that of the equal cross-section beam under the action of the unit bending moment. Then, the deformation of the variable cross-section can be calculated by using the calculation formula of the equal cross-section beam. Finally, Graphic multiplication is used to solve the stepped variable cross-section statically determinate beam and the function relation between bending moment and inertia moment ratio and variable cross-section length ratio is obtained by MATLAB. It is of great significance to the thin-walled supporting and protection by using the function between the bending moment and the parameter to determine the optimal supporting main beam.

Concrete distributor is one of the key equipment for the industrial production of concrete product parts. Its performance directly affects the product quality and production efficiency of precast concrete components, which in turn affects the level of architecture industrialization of China. At present, the domestic concrete distributor has a low degree of automation and a simple mechanical structure. There is too much manual intervention in the production. It is impossible to achieve a real automatic distribution. Also, BIM data cannot be shared with the control system, resulting in low production efficiency. This paper summarized these problems which are in the context of big data, internet of things and intelligence, and proposed the upgrade ideas for precast concrete components production equipment. In order to break through the bottleneck that restricts the stability, refinement and intelligent development of precast concrete components distribution. The research and exploration in BIM data analysis mechanical structure optimization and control system upgrade were conducted. Then the overall development of mechanical equipment that meets construction standards of China will be promoted.