bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Study on the Ultimate Bearing Capacity of Partially Overlapped CHS-to-SHS Welded N-Joints
Authors: Shu Xing Ping , Yuan Zhi Shen , Zhu Zheng Rong , Yao Yao
Published: October 2011

This paper presents the experimental and numerical results of the ultimate bearing capacity of partially overlapped tubular N-joints, which have circular hollow section (CHS) brace members welded to a square hollow section (SHS) chord member. Two partially overlapped N-joints were tested to failure under overlapping brace axial loading and chord axial loading. The failure mode of specimen N1 was the overlapping brace local bucking, and the failure mode of specimen N2 was the chord face plastification with chord side wall buckling. Meanwhile, weld fracture occurred on both specimens. Then, making use of finite element package program ANSYS, in which twenty nodes solid element was employed and the weld was simulated, elastic-plastic large deflection finite element analysis of the experimental joints was conducted. The experimental data were compared with the results acquired by finite element analysis and it was proved that ANSYS is feasible to simulate the connecting weld and analyze the static behavior of partially overlapped CHS-to-SHS welded N-joints.
Factors and Countermeasures Impacting Sound Insulation Performance of Light Steel Structure House Wall
Authors: Zhang Xin Zhong , Pang Rui Yan
Published: October 2011

The sound insulation performance of Light steel structure wall directly affects the quality of housing and people’s feeling. A theoretical analysis of the wall of light steel structure residential sound insulation performance is done, and some solutions in poor lightweight wall sound insulation measures is proposed.
Experimental Study on Seismic Capacity of Steel Encased Concrete Composite Frames
Authors: Du De Run , Dong Kun , Jiang Ji Tong , Yang Song
Published: October 2011

The low-cycle repeated load tests were conducted for two composite frames, with reinforced concrete column and steel reinforced concrete column, respectively. The performance of the composite frames such as the failure modes, ductility, energy dissipation ability, deformation restored ability, and resistant capacity is analyzed. Experimental results show that good seismic performance can be obtained by appropriate constructional measure which can meet the seismic design requirements. Based on the analysis of test data, the reliability of the beam-to-column connections is validated, and the seismic performance of composite frames is found to be influenced mainly by vertical anti-lateral force component. Besides, the form of steel reinforced concrete column is recommended to improve the structural ductility.
Study on Issues on Monitoring of the Construction of Tianjin Tower
Authors: Duan Xiang Sheng , Yang Yang , Li Zhi Wei , Gong Yu Jie
Published: October 2011

Tianjin Tower is the tallest building in North China. It is an out-of-code super high-rise building. Considering the special structure and safety factors during the construction, this paper describes the monitoring of the construction. The problems on numerical simulation model, creep calculation model and steel plate sheer wall welding during the construction monitoring have been discussed and corresponding solutions are given. Through the comparison and studies on the results of field monitoring, the solutions in this paper have provided practical advice on performance evaluation of the structure of Tianjin Tower and construction methods of Tianjin Tower, and are of certain significance in the reference for the construction monitoring of super high-rise buildings alike.
Test Research and Simulation Analysis about ECO-ECC Materials Repairing Concrete Beams
Authors: Jiang Guo Qing , Luan Hao , Duan Xiao Fang
Published: October 2011

In the actual project, ECO-ECC can be used in repairing bridge deck overlay, prefabricated lightweight partitions, structural coupling beams and slab reinforcement[1][2]. The use of fiber-reinforced composite materials ECO-ECC can implement outside paste reinforcement in damaged components [3][4], supplemented by appropriate construction methods (such as jet ECC process). The high liquidity of ECO-ECC, coupled with high decentralization of micro-fiber can solve the problem of old and new concrete interface bonding and restore the using functionality and security of the structure, and extend the use life. The maximum principal stress of PC, E70, E80 and E90 is 130με, 501με, 257με and 168με. The area of maximum principal stress decreases with the thickness of strengthening layer reduces. That explains that strengthening layer provide better ductility to prevent brittle failure.
Durability Environment Division of Concrete Structures Based on Combination of Fuzzy and Rough Set
Authors: Niu Di Tao , Luo Da Ming , Xing Guo Hua , Ma Hui
Published: October 2011

In this paper, fuzzy set and rough set theory were used to the research of durability environment division of concrete structures. Based on discretization of the measured data, the significance of attributes among rough sets was estimated instead of weight determination, and a relation data model about the durability effecting factors of concrete structures was established. A knowledge system was built through making attribute value into eigenvalue. During data analysis, the assessment of the regional factors was computed by analyzing the support and significance of evaluation method for the predicted object. The proposed approach overcomes the subjectivity of traditional weight determination method, After researching on durability environment divisions of concrete structures in Shenzhen city, the result shows that the proposed approach overcomes the subjectivity of traditional weight determination method, possesses much more objectivity and improved the accuracy and efficiency of comprehensive evaluation.
Shear Bearing Capacity Forecast of Reinforced Concrete Frame Abnormal Node Based on the BP Neural Network Theory
Authors: Li Hong , Hao Sheng Ling , Zhang Dong Fang
Published: October 2011

In order to forecast shear bearing capacity of reinforced concrete frame abnormal node on the basis of analyzing feedforward neural network theory, the complex nonlinear relationship, which is between shear bearing capacity of reinforced concrete frame abnormal node under the low cyclic loading and each major influence factor, is simulated by BP neural network, and the neural network prediction model is built. The comparison with the result of experiment has brought satisfying result. The method of shear bearing capacity forecast of reinforced concrete frame abnormal node based on the BP neural network theory is proved feasible and applicable.
Seismic Research of Continuous Rigid Frame Bridge under Cantilever Construction Method
Authors: Tang Xian Yuan , Hu Qiang , Yu Yong He
Published: October 2011

To research the effect of earthquakes of different magnitudes on continuous rigid frame bridge under cantilever construction method, combined with the newly promulgated seismic design rules of highway bridges in China, finite element model has been built by Midas software by using the response spectrum method and dynamic time history analysis method to analyze cantilever construction method of the various stages of seismic response analysis. The results indicate that the bending moments of root segments of cantilever beams and the bottom sections of piers change greatly. So it should be attached importance to in design.
Elasto-Plastic Properties of Panel Zones and Effects on Story Drift of Steel Frames
Authors: Guo Bing , Peng Xiao Tong
Published: October 2011

Using the plastic shear deformation of panel zones (PZs) to increase the ductility and seismic energy dissipation of structures is a common practice in most countries specifications. This makes PZs generally yielding before columns and beams, and the shear deformation of PZs is relatively large. In order to explore the elasto-plastic properties of PZs, tests of different types of beam-column connections under monotonic loads were conducted firstly. Focus of tests is to explore the influence factors on elasto-plastic properties of PZs. Then based on test results and existing research data, simplified calculation methods of PZs strength and stiffness in the elastic and elasto-plastic stage were derived, and bilinear relationship expression of PZs moment-rotation was also given. Finally, the simplified calculation method for considering the effects of PZs elasto-plastic shear deformation on story drift of steel frames was presented.
The 3D Seismic Pounding Effect of High-Pier Bridge Based on OpenSees
Authors: Meng Qing Li , Yin Xia
Published: October 2011

In this paper, a real high-piers bridge was taken as the example, the 3D nonlinear finite element model of this high-pier bridge is built based on OpenSees, then to do the analysis of seismic collision effects of the high-pier bridge under uniform excitation and multi-excitation considering the effect of traveling wave. And analyzing the reaction rule under different ground motions, and focusing on the differences of the effects of seismic pounding between uniform excitation and multi-excitation considering the effect of traveling wave. the seismic responses of high-pier bridge are closely related with its inherent dynamic characteristics and the spectral characteristics of ground motion and closer to the natural cycle of the bridge the main periods of ground motion is,greater the bridge collision response; traveling wave effect amplifies seismic pounding response, while the end of piers are adversely affected, exacerbating the damage. Although whether or not the traveling wave effect is harmful to the bearing, the traveling wave effect has obvious influences to bearing. Therefore, in the analysis of bridge seismic collision response it is necessary to consider traveling wave effect.
The Review about a New Type of Bridge Structure — Semi–Integral Abutment Jointless Bridge
Authors: Wang Tian Li , Li Qing Ning , Hu Da Lin
Published: October 2011

It was well known that expansion joint of a bridge was a weak part of structure, it led to early structure destroy and reduced the bridge life. Basing on Life-Cycle Design of bridge structure , a new type of optimum bridge structure --- Semi–Integral Abutment Jointless Bridge was put forward. Firstly the new bridge structure was defined and its performance was described. Then several problems that included temperature effect, the interaction of structure-soil etc were discussed about the application of the new bridge structure. Finally the conclusion is the Semi–Integral Abutment Jointless Bridge is a kind of durable bridge structure that has rational mechanical performance and great practical value.
Desorption Experimental Analysis and Modeling of Drying Shrinkage and Relative Humidity in Non-Saturated Concrete
Authors: Meng Ling Yun
Published: October 2011

Abstract. The paper investigates the gradient of relative humidity over time at different depth from dried surface and the relationship between relative humidity and concrete shrinkage. It shows that a drop in relative humidity over time is remarkable, and that drying shrinkage is linearly related to humidity. By measuring the weight of the sample and calculation of the capillary pressure, the relationship between the saturation and the capillary pressure is presented. Based on the experiment and Kelvin’s law, a model of shrinkage for non-saturated concrete taking the surface energy into account is presented. A comparison of computed and observed drying shrinkage is made, finding that the two values are in agreement very well.
The Fire Safety Analysis of Semi-Underground Public Building
Authors: Yan Ji Wei , Zhang Shu Ping
Published: October 2011

The fire design of semi-underground building is much strict according to the fire design of underground structure. Take the actual project of a Semi-underground building for example, evacuation distance of basement1 in this building over the standards. To solve the problem, the performance-based design uses the computer simulation to analyze the building. Using the simulated data judge the safety of the building. Then the paper gives advice of setting up the "Quasi safety zone" to solve the problem of evacuation distance. The paper discusses the fire safety of Semi-underground building and expects some advice to design of actual project.
A General Chain Equations of the Waterhammer in Liquid-Filled Piping Systems
Authors: Yang Ke
Published: October 2011

According to the general solution for waterhammer deriving by the author, this paper proved that the solution can be written in the form of the d'Alembert's wave functions. Some equations including the so-called the chain equation is derived with the help of the new solution. The periodical influence of the initial conditions on the results is discussed.
Application of Prestressed Concrete Box Girder with Steel Plate and Concrete Composite Strengthening
Authors: Yuan Zhuo Ya , Shi Xiong Wei , Feng Wei , Ke Liang Liang , Chen Li
Published: October 2011

In this paper, a formulation for calculating ultimate bending capacity was created. A nonlinear finite element model was established using ANSYS with right material parameters for prestressed concrete box girder with steel plate and concrete composite strengthening (SPCCS).A comparison was made between analysis results and function formula data, and results show that the numerical result s of nonlinear static analysis are in good agreement with the formula results. Effect of SPCCS and steel plate strengthening was compared, and the results show that SPCCS does more effective.
Effect of Filled-Concrete Height on Ultimate Strength and Ductility of Steel Tubular Bridge Pier with Partial Filled-Concrete
Authors: Wang Zhan Fei , Wu Quan , Sui Wei Ning
Published: October 2011

In the present of paper, four experimental steel tubular columns with partial filled-concrete under reversed cyclic lateral load and constant axial load were numerically analyzed by finite element package ABAQUS. Under certain conditions of the radius-to-thickness ratio Rt and the slenderness ratio λ parameters, effect of filled-concrete height on ultimate strength and ductility of this type bridge pier was investigated. These numerical results of tubular columns with partial filled-concrete were compared with the previous experimental results. It was found that these numerical results agree with the experimental ones very well. And these load-displacement hysteretic curves, which were obtained from numerical model, indicated that filled-concrete height had greatly affected the ultimate strength and ductility of steel tubular bridge pier with partial filled-concrete.
Comprehensive Mathematical Evaluation on Risk of Debris Flow
Authors: Liao Fang Wei , Liu Xiao , Liu Ping
Published: October 2011

Debris flow is one of the usual mountain geological disasters, and it is significant to assess and forecast its risk degree. The paper bases on statistical analysis of influence factors of debris flow risk degree, establishing 15 indexes to accurately assess debris flow risk degree. Furthermore, the evaluation index system is constructed by using analytic hierarchy process. And after combining the linkages between indexes, calculating each weight, and amending repeatedly with examples, finally the comprehensive mathematical evaluation on risk of debris flow is set up.
Construction Simulation Analysis for Suspend-Dome Structure of Pingshan Basketball Gymnasium for Universiade 2011 Shenzhen
Authors: Meng Mei Li , Wu Bing , Fu Xue Yi , Sun Can
Published: October 2011

Suspend-dome structure is adopted in Pingshan Basketball Gymnasium for Universiade 2011 Shenzhen. The suspend-dome is a prestressed structural system with the combination of rigid-flexible. Due to the less of actual projects and the lack of construction experience, the analysis of the whole construction simulation for the roof would be much important. Focused on the features of the project, considered the actual condition of the construction, the construction schedule and the tension sequence were chosen, the prestressed construction simulation analysis was carried through the infinite element calculation, the member force and deformation evolution was achieved from the analysis, which would be used to make sure the safety of the construction process. The key issues and relevant construction methods for the construction of the suspend-dome were summarized, which could be used as reference in the similar projects.
The Seismic Design of Staircase in Frame Structure
Authors: Zhang Peng Cheng , Yuan Qin
Published: October 2011

As the essential vertical transportation in multistory or high-rise building, stairs is very important. When2008, 5.12Wen-Chuan earthquake occurred, many staircases were seriously damaged especially in the multistory framework structures which were built in recent years. It seems probable that some common fault happened in the design work. In the multistory framework the stairs member may contribute stiffness as a "K"-shaped brace which effecting the deformation of the frame notably, triggering tension or compression to the stairs plate, however, the "K"-shaped brace effecting were neglected in the design courses. This paper analysis the seismic damage of staircase and stairs, puts forward in multistory framework, the design of stairs can choose "rigid" or "flexible" solvent. The suggested methods can be use either to repair the existing stair structure or to design stairs for new frame building in order to improve the structural function of stairs and the overall building.
Research on Fire Behaviour of a Lightweight Aggregate Concrete Composite Floor
Authors: Sun Hong Liang , Wang Xin Tang , Sun Ping Xin
Published: October 2011

To study the fire performance of the profiled sheet-light aggregate concrete composite floor subjected to fire load, study of fire response and post-fire bearing capacity of a profiled sheet-lightweight aggregate concrete composite floor subjected to dead load is carried out. Based on the experimental results, the fire performance and post-fire bearing capacity of the floor after exposure to fire are analyzed. It is shown that the failure form of the profiled sheet-ceramsite concrete composite floor after exposure to fire still exhibits higher bending capacity, and the ultimate value of the equivalent distributed load is up to 30.69kN/m2, which may be used as basis of strengthening and repairing of the profiled sheet-ceramsite concrete composite floor after exposure to fire.
Ground Motion Analysis in Nonlinear Soil Site with Random Media
Authors: Chen Yuan , Li Jie
Published: October 2011

In this article,by incorporating equivalent linearization method and the orthogonal expansion method into the wave finite element analysis of scattering problem, an analytical methodology for the evaluation of seismic response of nonlinear soil site with uncertain properties is proposed . Example is given to show the applicability of the methodology. The results show that the randomness of the site media has important effect on seismic site response , the randomness has greater influence on the variation of accelerations than on displacements. The coupling of the nonlinearity and the randomness of soil enhances the effect of randomness on the soil site.
Formation Mechanism and Stability Analysis of Bei’an-Heihe Expressway Expansion Project K178 Landslide
Authors: Jiang Hua , Shan Wei
Published: October 2011

Correctly analyze the formation mechanism and failure mode of the landslide and reasonably evaluate the stability of landslide, can provide scientific basis for landslide controlling. Employed the field investigation, field monitoring, indoor experiment and numerical simulation methods to carry a systematic study on the stability condition and formation mechanism of the Bei-Hei expressway expansion project K178 landslide, the results show that: the silty clay which is loose when dried, and is soft plastic when saturated glides along the surface of bedrock; the safety factor during surveying is 1.21, the landslide is temporarily in a steady state, when the water content of rupture surface soil is increased to 30.5% , the safety factor will reduce to below 1.0, the landslide will be instability; atmospheric precipitation, snowmelt water and seasonally frozen soil thawing water provide water for landslide, cracks and high permeability of main body soil provide passage for water infiltration, mudstone and sandstone with low permeability form aquifuge, silty clay above the aquifuge which is influenced by infiltration water to reach saturation forms rupture surface.
Study on the Testing Auxiliary System of a Large Scale Centrifugal Shaker
Authors: Wang Yong Zhi , Yuan Xiao Ming , Sun Rui
Published: October 2011

By special advantages and progress of dynamic centrifugal model tests, construction and development of large scale centrifugal shakers are driven. As one subsystem of a large scale centrifugal shaker, the testing auxiliary system is used to data acquisition, image acquisition and model making. The perfect design and construction of a testing auxiliary system must give a guarantee for dynamic centrifugal model tests. This paper outlines the components and function of the testing auxiliary system of a large scale centrifugal shaker. The basic design requirements and critical techniques relevant to data acquisition systems, image acquisition systems and containers are analyzed according to the characteristics of dynamic centrifugal model tests on a large scale centrifugal shaker, meanwhile, some specific conception and design suggestions are proposed. The results can offer some references for design of the testing auxiliary system of a large scale centrifugal shaker.
Analyses of Nonlinear Models under Low-Cyclic Loading of SRHSHPC Frames
Authors: Zheng Shan Suo , Shang Xiao Yu , Wang Wei , Li Lei
Published: October 2011

Based on the object-oriented finite element analysis software OpenSEES, a hinged 3-floor 2-span, SRHSHPC frames numerical simulation model was built up, under low cycle loading. Comparing the numerical simulation results with experimental data, the results show that four Gauss integral points of the Nonlinear Beam-Column Element with fiber - model can get best simulation effect. This study can provide theory basis for the SRHSHPC frames numerical simulation and the development of seismic performance.
The Solute Redistribution during Solidification of Al-Si-Mg Alloys
Authors: He Zhi , Zhou Hao Bin , Zhang Zhong Yao , Li Lan Yun
Published: October 2011

The solution redistribution was an important phenomenon during the solidification of multi-component alloys. The changing disciplines during solidification of different component Al-Si-Mg alloys were calculated in this paper. The calculations were coupled with CALPHAD technology. The interaction of solutes would change the solute redistribution coefficients during the solidification especially in the ends of solidification. So in the ends of the solidification, the slope of the curves turned to bigger and bigger. The results of the calculating of the eutectic fraction of the alloys show that errors exist under assuming the partition coefficients of solutes as a constant due to the interaction between solutes in ternary alloys. The predicted eutectic fractions of Al-Si-Mg alloys agree well with the experimental results for using the CALPHAD methods.
Study on Dynamic Characteristics of Long Span Continuous Bridge from Construction to Completion Constructed by Cantilever Method Based on Perspective of Earthquake Resistance
Authors: Zheng Yu Guo , Yuan Wan Cheng
Published: October 2011

Based on the perspective of earthquake resistance, the dynamic characteristics from construction to completion is analyzed and compared with each other for three typical long span continuous girder bridges with different types of piers constructed by balanced cantilever method, the vase-type solid pier, the thin-wall type hollow pier and the double-column type solid pier. The variation law of the dynamic characteristics along with the construction stages is obtained and the comparison law of the dynamic characteristics is obtained among the three bridges. It shows in a great degree that the seismic performance analysis and the seismic design nowadays, which are only based on the 1st period and mode in the completion state of the bridge, are not reasonable very much. The seismic performance analysis and the seismic design should consider all construction stages for the bridge constructed by the balanced cantilever method.
Feasibility of Hydrogen Production by a Continuous Two-Stage (Dark/Dark) Fermentation System
Authors: Qu Yuan Yuan , Guo Wan Qian , Ding Jie , Ren Nan Qi
Published: October 2011

Anaerobic hydrogen production in a continuous two-stage fermentation system was studied. Two continuously stirred tank reactors (CSTR) were employed to evaluate performances of the system. The first stage was fed with molasses wastewater, and the effluent discharged from the first stage was subsequently fed into the second stage. The hydrogen production rate (HPR) in the second stage achieved a remarkable increase from 1.76 L/d to 6.45 L/d during the operation by re-utilizing the residual substrates from the first reactor effluent. The two stages showed a similar metabolic pathway for biohydrogen fermentation. The hydrogen production yield (HY) and acidification efficiency increased markedly by more than 70% and 50% respectively, which indicated the hydrogen recovery and anaerobic acidification of organic substrates can be improved by the combined continuous two-stage hydrogen production process.
Experimental Study on Activated Sludge Form Sewage Treatment of Different Oxygen Gradient Reactor
Authors: Tian Xi , Bian De Jun , Ren Qing Kai , Qu Hong , Wan Li Guo , Zuo Yan
Published: October 2011

It used dissolved oxygen meter to detect dissolved different oxygen concentration within wastewater treatment reactor and analysed reasons for the formation of oxygen concentration gradient. In order to learn more about activated sludge form of different oxygen gradient in the reactor, biological microscope operated in characteristics of microfauna and activated sludge floc in the reactor has been studied. The results showed that Vorticella and Rotifera could grow normally in the high and low regional areas; there are more abundant micro-fauna species in the area of low oxygen, and the microfauna was more mature than those in the area of high oxygen; activated sludge was brown and floc size was small in the areas of high oxygen, activated sludge was black and floc size was big.
A New 3-D Unit Cell Model Used in Homogenization Estimation of Effective Properties of Particle-Filled Composites
Authors: Ouyang Yong , Hu Xiao Ling , Liu Xiu , Luo Wen Bo
Published: October 2011

A new 3D unit cell model is developed for homogenization calculation of composites containing randomly dispersed ellipsoid inclusions. The new unit cell is constructed using the Ansys Parameter Design Language (APDL), taking the inclusion volume fraction, inclusion orientation and spatial dispersion as variables. A series of unit cells containing multiple ellipsoids, showing random distributions in particle size and position, were constructed and used for finite element calculation at microscale, the effective modulus of the composites with periodic microstructures, which modeled by the unite cells, were then estimated by homogenization. The influences of particle volume fraction and the particle stiffness on the effective elastic modulus of the composites were examined. The estimated results were compared with different particle volume fractions were calculated, and the calculated data was compared with other classic models.
Experimental Study on Shear Behavior of Meshwork Cold-Formed Thin-Wall Steel RC Shear Wall
Authors: Chen Zhong Fan , Gao Wei
Published: October 2011

CTSRC(cold-formed thin-walled steel reinforced concrete) structure system is one new type of industrial structure system，which uses the cold-formed thin-walled steel to replace the vertical steel bars in common reinforced concrete shear walls. This paper conducts some study on the shear behavior of walls of high rise civil building. Experiment study on both one low CTSRC and one low RC wall of equivalent reinforcement subjected to low-cycle reversed horizontal load are tested, which includes description of experinment pheonomenon, analysis of loading and failure model, load-displacement hysteresis loop curves, load-displacement skeleton curves and analysis of strain. The experiment results indicate that under the same condition there is no difference between the shear property of CTSRC and RC wall basically on failure mode and shear behavior. At last, this paper provides some suggestions about further research contents of CTSRC structure system.
Corrosion Rate Evolution in Concrete Structures with Hydrophobic Agents Exposed to the Marine Environment
Authors: Cao Wei Qun , Fan Hong , Zhao Tie Jun
Published: October 2011

In many cases, service life of reinforced concrete structures is severely limited by chloride penetration until the steel reinforcement. Today, concrete with high resistance with respect to chloride penetration can be produced by internal hydrophobic treatment. The aim of this study was to fill this gap in regards to reinforced concrete structures inserted in a marine environment. Results indicated the efficacy of the hydrophobic agents in cases where capillary suction is the mechanism of water penetration. However, when the transport mechanism is permeability this product is not advisable. Moreover, it was demonstrated that the chloride diffusion coefficient is reduced by the hydrophobic agents, and the corrosion rate of reinforcement could be well protected in the treated concrete with hydrophobic agents of silane. The durability of reinforced structures can be considerably increased and can be accurately designed by the application of an appropriate and optimized protective layer.
Performance Evaluation of BRA Modified Asphalt Based on Analysis of Rheological Property
Authors: Li Rui Xia , Hao Pei Wen , Wang Chun
Published: October 2011

With the experiments of dynamic shear rheometer(DSR), bending beam rheometer(BBR) and Brookfield rotary viscometer, the rheological performance of Buton Rock Asphalt (BRA) modified asphalt is tested and analyzed. The results indicate that the high temperature PG grades, the anti-rutting indicator and the viscosity are all increased, the high temperature stability is enhanced greatly and the temperature sensitivity is reduced after the addition of BRA modifier. Furthermore, the change rate increases with the increase of the additive; the creep stiffness modulus increases and low-temperature performance decreases at a low temperature, so the dosage of BRA should be appropriately considered in the process of application.
Synthesis and Humidity Controlling Properties of Hydrotalcite/poly (sodium acrylate-acrylamide) Composite
Authors: Wang Ji Hui , Dong Fei , Ren Shu Ping , Guo Meng Jie
Published: October 2011

Hydrotalcite/poly(sodium acrylate-acrylamide) composite was synthesized by using inverse suspension polymerization method under different hydrotalcite content, neutralization degree and ratio of monomer with orthogonal experiments. The surface morphology, structure and humidity controlling properties of composite were observed and determined. The results show that hydrotalcite/poly (sodium acrylate-acrylamide) composite is in an irregular block like structure with different size. During the polymerization process, acrylate and acrylamide monomers are successfully intercalated into the interlayer of hydrotalcite, and the distance of (003) hydrotalcite plane is increased from 0.766nm to 1.146nm. The impact of three factors on the humidity controlling behavior of composites increases by the order of ratio of monomer, hydrotalcite content and neutralization degree. The optimum preparation parameters are hydrotalcite content of 4%, neutralization degree of 90% and ratio of monomer in 9:1.
Discarded Tire Implications in Reinforced Slope
Authors: Li Li Hua , Tang Hui Ming , Xiao Ben Lin
Published: October 2011

Discarded tires used as reinforced materials have distinctive merits, such as high tensile strength, good anti-friction, fine flexility and durability, which can be used in reinforced wall, embankment and slope etc. some successful applications of discarded tire in reinforced slope are introduced, which have not only obtained significant economic benefits, but also resulted in good social and ecological benefits. The environment stress resulted from the world black pollution of discarded tires may be relieved through these new geotechnical applications. Different reinforced pattern of discarded tires are compared. The result has shown that discarded tire used for reinforcement is a particularly useful method. The settlement need to be given attention during reinforced engineering. Clay soil is averted as reinforcement with discarded tires. The tire with inside wall removed and backfilled with sandy soil is a good reinforced pattern.
Application of Chemicals in the Restoration of Monuments
Authors: Huang Wen Zheng
Published: October 2011

Monuments are precious historical and cultural heritages, they are non-renewable cultural resources, the authenticity of monuments lies in the value of cultural relics, protecting the monument’s historical value and reflecting the complete history characteristics in particular historical period are the restoration principles of monuments. This paper proposed the attentions of applied chemicals in the restoration of monuments by introducing the application of chemicals in monument’s anti-corrosion treatment of wooden components, reinforcement of wooden components, protection of masonry as well as masonry reinforcement etc. Chemicals can effectively protect the unique historical, scientific and artistic value of monuments, chemicals and chemical technology will have broad application prospects in the field of monument restoration technology.
Research on Strengthening Mechanism of Bamboo Fiber Concrete under Splitting Tensile Load
Authors: Qi Feng , Pan Jian Yun , Yang Bo
Published: October 2011

Bamboo fiber concrete is a type of architectural material. Because of its fast growth and environmental protection, bamboo fiber concrete attracts much attention from researchers and industries. However, research on bamboo fiber concrete is not enough which greatly affects its applications in engineering. Based on the splitting tensile test of bamboo fiber concrete, the formulas of splitting tensile strength are presented using composite material theory and fiber spacing theory respectively. A comparison of the theoretical values of splitting tensile strength with those of test is made. It is found that the formula deduced from composite material theory leads to severe errors because of its unrealistic hypothesis. Therefore the composite material theory is inappropriate to explain the strengthening mechanism of bamboo fiber concrete. On the other hand, fiber spacing theory not only has higher accuracy but also reflects the effect of fiber content and length-radius-ratio on the splitting tensile strength of concrete. So the fiber spacing theory is adapted to study the strengthening mechanism of bamboo fiber to concrete.
Scrap Tires Recycling in Landscape Engineering
Authors: Kang Zhen Zhen , Zhang Bing Jun
Published: October 2011

With rapid development in automobile industry and increasing environment problems, a difficulty confronting many countries is how to recycle scrape tires. By analyzing the scrap tires directly reclaimed and reused application in landscape engineerings such as Flower Pots, Swings, Patio Furniture, Landscape decoration, Climbing nets, Retaining Walls, Sculptures, Theme parks and more. It suggests old tires can be converted into something truly useful and even valuable and artistic and can be used in simple, cost-effective and environmentally-friendly way.
Experiment Research on Compressive Strength of Specified Density Steel Fiber Concrete
Authors: Zhang Pan , Zhang Yan Kun , Li Xiao Hu , Guo Zhen Lei
Published: October 2011

Based on the experimental research, the prism compressive strength and cubic compressive strength of specified density steel fiber concrete are studied. Through regression analysis, the influence of type of steel fiber, volume content of the fiber and substitution ratio of lightweight aggregate is studied. According to the test results, the formula of prism compressive strength and cubic compressive strength is given.
The Influence of High Performance Concrete on Low-Carbon Economy
Authors: Miao Chang Wen
Published: October 2011

The demand for high performance concrete is increasing nowadays. The service life of high performance concrete has significant effect on the consumption of energy and resources. Adding good chemical and mineral admixtures to regulate and optimize the microstructure of concrete can ensure the service life of concrete structures and save great amount of cement simultaneously. It is a good way to turn waste into resource and turn the harmful into the beneficial.
Experimental Study on Coefficient of Thermal Expansion of Road Concrete
Authors: Zhang Yan Cong , Tian Bo , Wang Da Peng , Wang Ji Liang
Published: October 2011

A method for determining the coefficient of thermal expansion (CTE) of concrete with optical lever system is introduced. In order to improve the system of traditional optical lever, vernier caliper was used instead of the scale plate to deduce the precise formula according to theories. The experiment was carried out to test the CTE of concrete with different aggregates. The results show that: when aggregate content was equivalent, the CTE of concrete increased with that of aggregate. Type of aggregate affected the CTE significantly.
Thinking Caused by Rereading Howard's Garden Cities of Tomorrow after a Century
Authors: Liu Li Xin
Published: October 2011

Howard's Garden Cities of Tomorrow is the first professional book of modern city plan in general, but there are many misunderstandings of the book and writer today. To be strict, Garden Cities of Tomorrow is not a book of city plan simply and Howard is not a traditional city planner. Although Howard's idea of “Sociable Cities” involves clear thinking of social reformism utopian, Garden Cities of Tomorrow is the most important and influential masterpiece in the history of city plan in the 20th century.
Effect of Calcium Dissolution on the Fracture Properties of Concrete Exposed to Nitric Acid Environment
Authors: Wang Hai Long , Guo Chun Ling , Sun Xiao Yan
Published: October 2011

The effect of calcium leaching by nitric acid on fracture properties of concrete was experimentally studied. The double-K fracture parameters were investigated using three-point bending beams, and the deterioration regularity of fracture properties of concrete chronically attacked by nitric acid was gotten on basis of these results. The load-crack mouth opening displacement curves under different nitric attack periods were obtained by pasting some strain gauges onto the pre-crack tip. On basis of the double-K criterion, the unstable fracture toughness as well as the initial fracture toughness was calculated according to the critical crack mouth opening displacement, the unstable fracture load and initial cracking load which can be obtained from the test. The experimental results indicated that the ratio of the initial fracture toughness to the unstable fracture toughness varied between 0.47 and 0.61 approximately. Both of the unstable fracture toughness and the initial fracture toughness decrease with attack period especially during the early 60 days, then drop to a stable trend gradually. In addition, the initial fracture toughness is less sensitive to acid attack compared with the unstable fracture toughness.
Application of the Ground Source Heat Pump in a Middle School
Authors: Xu Ping Ping , Fang Min , Yao Jin Xiu
Published: October 2011

This paper briefly introduces the design and application of ground source heat pump system in a middle school’s history exhibition room and reading room and analyses the project costs and operating costs. After comparison, it shows that the operating cost of the ground source heat pump system is 42560 YUAN lower than that of VRV system a year.
Research on Durability of Coastal Concrete Bridges
Authors: Lei Jun Qing
Published: October 2011

The work presented in this paper focuses on durability of concrete bridges, which is worldwide concerned nowadays because concrete bridges will deteriorate and damage under the natural environment and the long-term usage. The shortage in bridges durability performance will result in severe environment problems; energy sources matters and economic issues. Quickly developed coastal cities and transportion, due to large-scale expansion of themselves and exploitation of ocean resource, have to face rigorous marine climate. Hence, the studies the authors have performed showed that as a civil engineer it is important to learn the research and countermeasure actuality on durability of coastal concrete bridges. According to current research, the existing problems as well as objectives for further studies are also indicated .
Theoretical Proof for the Relationship between Cable-Strut Structures’ Stiffness and Prestress
Authors: Feng Qing Xing , Qu Chen
Published: October 2011

From the point of strain energy, an important conclusion has been derived and proved that cable-strut structure stiffness will be enhanced with the increase of prestress, provided that the cable-strut structure is within the scope of linear elasticity, and external loads' work will be completely absorbed and transformed into structural strain energy.
The Layout and Form Design Research on BIPV External Sun-Shading Skin in Hot-Humid Areas
Authors: Xiao Yi Qiang , Ren Ting
Published: October 2011

Building external sun-shading is an important building energy efficiency measure in hot-humid areas. Integrated photovoltaic sun shading, which is of energy saving as well as power production, is one method with great potential for sustainable development of building. This paper extends the external sun-shading modules design and explores the BIPV design possibilities in the area by discussing the combined building skin strategy in hot-humid areas, photovoltaic external sun-shading modules layout and the micro-structure technical analysis. The model is optimized and the specific application in construction is determined through the software simulation of solar radiation shading, indoor illumination effects and photovoltaic shading .The reasonable combination of photovoltaic sun-shading modules and the battery arrangement with different light transmission rate enrich the possibility of the building skin space in architectural heat shielding and aesthetic design.
Surface Settlement and Influence on Xi’an City Wall due to Xi’an Subway Line 2 Tunnel Construction
Authors: Li Jun Lian , Zheng Jian Guo , Yao Yang Ping
Published: October 2011

This paper refers the case project of the Xi'an Subway Line 2 tunneling through the South Gate area of the Xi'an City Wall, has researched the surface settlement due to tunnel construction, and simulated the whole shield tunnel by using Flac3D numerical analysis. This paper has obtained the law of surface settlement and the influence on the City Wall in the tunnel construction by analyzing the calculation results, and simulated the effects of three protective measures which will be used in the South Gate area. The results showed that the surface settlement ratio after the piles and chemical grouting reinforcement was lower by about 25% than no reinforcement. The monitoring data showed that the result of model calculation was reasonable, and the protective measures in Condition 3 are feasible and effective.
Research and Application of Energy-Saving Design Technologies in Science Center Building
Authors: Xu Yong , Zhang Ji Chao
Published: October 2011

According to the target of a science center building, some energy-saving technologies and relevant principles phases in architectural planning and design phase, architectural design and construction phase, and so on. With the requirements of energy-saving technologies and an environmental protection technology, some successful experience of Guangdong science center which named as the largest science center building of current China discussed. As a result, the energy-saving science center building design methods came into being, which includes natural ventilation techniques of central yard, optimization technology of enclosed structure, photoelectric curtain wall technology and solar power and so on.
Performance Study on Triple Square Steel Tube Buckling-Restrained Brace with Different Notch of Core Element
Authors: Tang Rong , Zhou Yun , Deng Xue Song , Lin Shao Ming
Published: October 2011

According to the philosophy of “partially weaken the core element of the BRB to protect the other part”, 12 specimens of the Triple Square Steel Tube Buckling-Restrained Brace (TSST-BRB) were designed with which the core element had notched. ABAQUS finite element method was used to investigate the performance of TSST-BRB with different notched kinds, number, length and depth of the core element. The analysis results indicated that the core element with annular notch was conducive to reduce the stress concentration of ends, and dissipate energy under tiny displacement. Two notches of the core element were better to reduce the peak stress of the notched segment and the stress concentration of ends. The length of notch should be controlled on 13.3%~20.0% of the length of core element. The energy dissipation capacity, yield displacement and yield capacity of the TSST-BRB were significantly influenced by the depth of notched core element. The depth of the notch should be controlled on 10%~23.3% of the thickness of core element.
A New Cost Effective Building Material: Compacted Wheat Straw Block
Authors: Liu Fu Sheng , Fan Jun , Bian Han Bing
Published: October 2011

In this paper it is shown that compacted wheat straw block is a cost effective building material in China. Wheat straw is renewable resource and ecological material, when used as building material; it is less energy and material consumption. The compacted wheat straw block has a small thermal diffusivity and good fire resistance. The hydraulic properties will guarantee a comfortable humidity of in door air, and protect the material from rot, and ensure the durability of the construction. The mechanical properties will also increase the structure safety. It is absolutely a cost effective building material.
Heating Performance Investigations on Two Applications of a Solar Assisted Air Source Heat Pump System
Authors: Wang Yu , You Yu Wen , Zhang Zhi Gang
Published: October 2011

A solar assisted air source heat pump (SAASHP) system is proposed to improve heating performance of air source heat pump (ASHP).The proposed system has been applied in two buildings, a series of experimental investigations were conducted in the both applications, it indicated that the SAASHP system gets better heating performance than ASHP system, the coefficient of performance (COP) gets 10% and 65% increase respectively in two applications. It is also concluded that the ratio of solar collector area to construction area significantly affects the improvement of heating performance in SAASHP system. This work may promote further research and more applications of SAASHP system.
Research on the Sustainable Use of Water Resources in the Urban Planning of Yinchuan
Authors: Zhang Ju Ping , Zhang Wei Jiang , Li Juan
Published: October 2011

With the accelerating of the process of urbanization and the rapid increase of the economy and society, the shortage of water resources is becoming more and more serious, and the conflict between the water resources and the economic development is becoming more and more conspicuous. Based on an analysis of the current situation and problems about the water resources in Yinchuan, the writer explores the issue of sustainable use of the water resources in the urban planning and makes proposals on the solutions accordingly.