bluuebunny/crossref_metadata_2025 huggingface dataset:
Test Study on the Rigidity Degradation and Energy Dissipation of High-Strength Reinforced Concrete Columns with Central Reinforcement
Authors: Dong San Sheng , Lei Zi Xue , Zhao Jun Hai
Published: December 2010

Based on the pseudo-static test of 6 high-strength RC columns with central reinforcement skeletons, this paper studied their hysterisis performance, degradation of strength and rigidity, and energy dissipation capacity, with the affecting factors analyzed. The result shows that the central reinforcement skeletons can compensate for the low plasticity and brittle failure susceptibility of high-strength concrete so that all the specimens have stable strength, slow rigidity degradation and high energy dissipation capacity at later stage of loading; the larger the core areas the higher the strengths and ductility of the specimens, but slightly faster the degradation of strength and energy dissipation capacity as compared with the specimens with smaller core areas; the spacing of ties, longitudinal reinforcement ratio of core area both influence the strength degradation and energy dissipation capacity of the specimens, but they have little effect on their strengths.
Seismic Response Analysis of Substation Involving Interaction of Main Structure-Electrical Equipments
Authors: Wen Bo , Niu Di Tao
Published: December 2010

The nonlinear dynamic response analysis of substation with structure-equipments interaction is studied in this paper. The results comparing with that of no interaction are shown that it’s necessary to considering structure-equipments interaction in substations. In frequent earthquakes, the structure-equipments interaction in substation is inconspicuous and the traditional equivalent load method is feasible. However, in strong earthquakes, the electric equipments really participate in the dynamic response and operate the reaction on main structure and the action goes against the main structure seismic design and couldn’t be ignored. In this condition, the traditional equivalent load method will be insecure any more. Because of the visible torsional response effect, the seismic ability of the corner columns in structure should be increased. The research results can be referenced by similar lifeline system.
Seismic Reliability of Long-Span Bridges Based on the First Order Reliability Method
Authors: Jia Bu Yu , Yu Xiao Lin , Zheng Heng Bin , Yan Quan Sheng , Li Wei
Published: December 2010

In this paper, first order reliability method (FORM) is generalized to the seismic reliability analysis of long-span bridges and the first excursion probability of a single tower cable-stayed bridge is studied. The seismic motivation is firstly dispersed as a series of random variables. Then the cross velocities on the dispersed time points can be obtained by solving the motivation of the design checking points with FORM. The upper bound of first excursion probability is also obtained by integrating the cross velocities at different time. The results show that the seismic reliability analysis method based on the FORM is feasible and effective to solve the first excursion probability problem. The single tower cable-stayed bridge studied in this paper has a higher reliability under strong seismic.
Dynamical Response of Circular Tunnel with Steel Lining under the Action of Blasting Vibration
Authors: Yi Chang Ping , Lu Wen Bo , Feng Ling , Wang Gang
Published: December 2010

The wave function expansion method is used to analyze the interaction process of the blasting seismic wave and the adjacent circular tunnel with steel lining, the stress expression, displacement expression and vibration velocity expression of circular tunnel under the action of blasting vibration are deduced, the stress, displacement and vibration velocity distribution of surrounding rock mass and steel lining are presented under the definite condition. In terms of the stress and vibration velocity distribution and the tensile strength of the rock mass, the critical failure vibration velocity of surrounding rock mass is obtained.
An Improved Three-Strut Model for Masonry Infills in RC Frame Structures
Authors: Zhai Chang Hai , Wang Xiao Min , Li Shuang , Xie Li Li
Published: December 2010

In Wenchuan Earthquake, masonry-infilled frames have the quite critical failures. In this paper, the reason of the failure phenomenon is analyzed and the influence of the infilled wall to performance of the frame is highlighted. An improved three-strut model for masonry-infilled frame structures is presented. Then, two RC frame specimens, which are modeled by the presented three-strut model and force-based beam-column element combined with fiber section considering compression-bending coupling in Opensees, are analyzed. The analytical results agree well with the experimental results. It is shown that the presented three-strut model is sufficient to simulate the performance of the infilled wall.
Characteristics of Wind Loads on Spherical Shells with Large Rise-Span Ratio
Authors: Qiu Ye , Sun Ying , Wu Yue
Published: December 2010

Characteristics of wind pressure distributions over the spherical shell with 3/4 rise-span ratio have been investigated based on the data obtained from a wind tunnel experiment. A discussion of the spectral characteristics including shape of wind pressure spectra, reduced frequency corresponding to the peak spectral amplitude, and spectral slope in high frequency range is also made. The results show that the normalized pressure spectra has a broadband peak at a reduced frequency between 0.15 and 0.50, the slope of Sp( f ) in a high frequency range varies from -1.85 to -0.30 and the reduced peak frequency depends on the tapping locations. Though spectral patterns change from place to place, standard normalized spectra associated with various zones of spherical shell could be appropriately classified based on identical spectral characteristics. On this basis, an empirical spectral equation is figured out including three parts which represent the contribution of approach turbulence, turbulence induced by separation on the top of spherical shell and wake turbulence respectively. The accuracy of model is verified by comparison with the measured spectra results.
Seismic Damage Prediction of Multistory Brick Buildings Based on RBF Neural Network Model
Authors: Wang Ling , Sun Li , Kong Dan Dan , Liu Xi Yuan
Published: December 2010

Seismic damage prediction of multistory brick buildings is a multi-factor nonlinear complex problems, this paper analyzed the deficiencies of the traditional methods for predicting the seismic damage, so a prediction model of multistory brick buildings based on RBF Neural Network model is established, RBF network structure elements and parameters are studied and obtained. With examples the research proved that the prediction results are similar to the actual seismic damage to multistory brick buildings by the RBP neural network model, the analytic method and process discussed in this paper can also be applied to seismic damage prediction of brick buildings of urban earthquake disaster prevention planning.
Static Elasto-Plastic Analysis of Buildings with Steel Tower on Top under Rare Earthquake
Authors: Hu Xiao , Gao Yong Tao
Published: December 2010

The earthquake resistant behavior of buildings with steel tower on top is different from ordinary buildings. In order to investigate the deformations, internal force and damage of structure under rare earthquake, based on a case of Shifang Telecom Building (STB) under 5.12 earthquake, the static elasto-plastic analysis is carried out. This paper compares the seismic behavior of structure under different loading cases, and studies the weakness and plastic hinge of the building. The result shows the structure can meet the requirements of non-collapse under rare earthquake, the top steel tower can amplify the seismic effect, and numerical simulation tallies with the reality.
Dynamic Response of Shallow Buried Tunnel Subjected to SH Wave
Authors: Chen Zhi Gang
Published: December 2010

The dynamic stress concentration on quadratic and U-shaped cavities in half space, which are similar to the cross-section of the tunnels, is solved in this paper impacted by SH-wave. The analytical solution for the cavity in elastic half space is gained by the complex function method. In the complex plane, the scattering wave which satisfies the zero-stress condition at the horizontal surface can be constructed, the problem can be inverted into a set of algebraic equations to solve coefficients of the constructed scattering wave by least square method. For the earthquake-resistance researches, the numerical examples of the dynamic stress concentration around the quadratic and U-shaped cavities impacted by SH-wave are given. The influences of the dynamic stress concentration by the incident wave number and angle, the depth and shape of the cavity are discussed. It is showed that the interaction among the wave, the surface and the shallow buried tunnels should be cared in half space. In this situation, the dynamic stress concentration around the tunnel is greater obvious than the whole space.
Optimum Control System for Seismic and Aerodynamic Flutter Response of Cable-Stayed Bridge Using Magnetorheological Dampers
Authors: Mohamad El Katt , Raafat Shaker , Younis Kassem
Published: December 2010

Control of cable-stayed bridge flutter for earthquake and aerodynamic hazard mitigation represents a relatively new area of research. This paper proposes a new optimized smart control system to mitigate the cable-stayed bridge flutter due to seismic and aerodynamic vibration. A Magnetorheological (MR) fluid damper, which belongs to the class of controllable fluid dampers, is proposed for use in a control strategy for mitigating its effect on the cable-stayed bridge. Genetic algorithm is adopted to determine the flutter acceleration levels, and corresponding forces of MR dampers. The optimized forces values from MR dampers are studied under the effect of five strong earthquakes recorded, known as El-Centro, Mexico City, San Fernando, Ker Country, and Northridge earthquakes. The time delay between the monitoring system and the actuator response is also studied. The simulation and optimization results shows that the proposed control strategy using MR dampers is the promising one of the applicable control methods to reduce the seismic and aerodynamic flutter vibration of the stayed bridge.
Study on the Method of Structural Seismic Performance Evaluation Based on the Damage Spectra
Authors: Teng Jun , Tu Hu Bing
Published: December 2010

Park-Ang seismic damage model is increasingly concerned due to it considers not only maximum elasto-plastic deformation, but also low cycle fatigue accumulated hysteretic energy, while research on the method of seismic performance evaluation based on the model is still rare. Therefore, a new evaluation method on the basis of damage spectra is proposed in this paper. Damage spectra of site I considering three kinds of ultimate deformation ductility factor are built firstly, and then transformation relationship between damage of MDOF and SDOF of frame structures is researched. Lastly, procedure of seismic damage evaluation on the structure is proposed. An example is used to confirm the validity of the spectra-based seismic performance evaluation method. The example analysis shows that: the method proposed here is reasonable to consider the impact of the cumulative hysteretic energy on the structural damage. The results from the method have good consistency with the time history analysis results. It can assess the extent of structural damage from the statistical viewpoint.
Research on Simplified RC Frame Column Model under Blast Load
Authors: Wang Xing Guo , Ge Nan , Wang Cui Min , Su You Po
Published: December 2010

An overall numerical model for a reinforced concrete frame was established and in parallel, a group of simplified models were established for the same structure according to the particular characteristics of the subjected load such as impact load, dynamic load and quasi-static load, to investigate their dynamic behaviors. Results show that it is reasonable to introduce the simplified models for reinforced concrete frame in analysis work.
Evaluation of Intensity Measures for Pulse-Like Ground Motions
Authors: Zhou Jing , Chen Kai Liang , Zhao Lian Heng
Published: December 2010

The correlation between intensity measures (IM) for pulse-like ground motions and nonlinear deformation demand of single-degree-freedom-systems (SDOF) is researched, and the efficiency of IM is described. Based on dynamic time analysis of SDOF systems subjected to 72 pulse-like ground motions, the present study investigates the variation of the correlation coefficient between IM for pulse-like ground motions and maximum nonlinear deformation demand of SDOF with the constant-ductility or constant strength system setting. Linear regression analyses are performed on these results to identify the efficiency of peak ground velocity (PGV) and spectral acceleration Sa(T1), which is used as IM for pulse-like ground motion. The study shows that IM of pulse-like ground motions depend distinctly on the system period, ductility levels and strength reduction factors have important influence on the correlation and dispersion, and Sa(T1) and PGV are relatively the good IM for pulse-like ground motion.
Analysis of Dynamic Response of High Rockfill Embankment under Seismic Loads
Authors: Yang Cheng Zhong
Published: December 2010

To reveal the stress-strain properties of Gangou high rockfill embankment with 71m high under seismic loads and provide the reference for its security evaluation and the seismic reinforcement design. By simplifying the high rockfill embankment as the plane problem, establishing two-dimensional finite element model, inputting EL Centro and applying seismic response spectrum method, the dynamic response of high rockfill embankment under seismic loads were simulated. The results show that: With the increase of embankment height, the dynamic response presents increasing tendency; The maximum displacement occurs on the right side of the embankment top, t1474he maximum acceleration appears at the middle of embankment slope. From the view of seismic design, the right side of the embankment top and the middle of embankment slope are the focus of seismic design.
Effect of Pounding at Expansion Joints on Seismic Response of Long-Span Suspension Bridge under Strong Earthquakes
Authors: Deng Yu Lin , He Xiong Jun
Published: December 2010

For a long-span suspension bridge, owing to a flexible structure system, the seismic displacement at the end of the deck may severely exceed the allowance under earthquake which due to the occurrence of the pound between the main span and the approach span usually which can causes the collision of falling-beams and structures. In this paper, based on the pounding phenomenon at expansion joints of long-span suspension bridge under strong earthquake and employing a typical long-span suspension bridges. With the time history analysis method of determining the nonlinear seismic responses, the pounding effects of adjacent girders at expansion joints on seismic responses of long-span cable-stayed bridge were studied. The results indicate that pounding can amplify the seismic demand of piers of the approach span and can also amplify the displacement of beam of the approach span, the relative displacement between main span and approach span and the hinge seat width of beam of approach span obviously and it causes easily the collision of falling-beams and structures under earthquakes.
Dynamic Analysis of Slanting Type Five-Span Continuous CFST Arch Bridge without Wind Tied-Bracing
Authors: Wang Hai Liang , Yang Xin Lei , Ren Quan Chang , Dong Peng
Published: December 2010

The concrete-filled steel tube (CFST) member has many advantages compared with the ordinary structural member made of steel or reinforced concrete. Continuous confinement provided by the steel tubes prevents excessive spalling of concrete and the concrete filled inside the steel tubes prohibits local inward buckling of the steel tube wall. This paper presents the dynamic response of a slanting type CFST arch bridge without wind tied-bracing. Effect of stiffness ratio between slanting arch and vertical arch on seismic performance was discussed.
Research on Prediction Method of Steel Frame-Reinforced Concrete Shear Wall Hybrid Structure Earthquake Response Based on Energy Concept
Authors: Pei Xing Zhu , Wang Wei
Published: December 2010

The basal theory of energy method is introduced, which makes use of the idea of energy balance to study the earthquake response of structures. Because of the high stiffness and low-cost of the steel frame-reinforced concrete shear wall hybrid structure, it is being widely used. But the study of the earthquake response prediction method of the structure has not been done yet. In this paper, energy method is used to study the earthquake response of the steel frame-reinforced concrete shear wall hybrid structure. A steel frame structure and a steel frame-reinforced concrete shear wall hybrid structure have been designed. The shear wall in steel frame-reinforced concrete shear wall hybrid structure is simplified as a column for easier study. In order to evaluate the results of the energy method, the time history analysis method is also used to study the earthquake response of the two structures. The shear coefficient, maximal interlaminar displacement and damage ratio of the two structures are studied. After comparison, it is found that the results of energy method and the time history analysis method are almost the same. The energy method can be easily used to study the earthquake response of the steel frame-reinforced concrete shear wall hybrid structure.
Geotechnical Seismic Isolation System - Experimental Study
Authors: Xiong Wei , Tsang Hing Ho , Lo S.H. , Shang Shou Ping , Wang Hai Dong , Zhou Fang Yuan
Published: December 2010

In this study, an experimental investigation program on a newly proposed seismic isolation technique, namely “Geotechnical Seismic Isolation (GSI) system”, is conducted with an aim of simulating its dynamic performance during earthquakes. The testing procedure is three-fold: (1) A series of cyclic simple shear tests is conducted on the key constituent material of the proposed GSI system, i.e., rubber-sand mixture (RSM) in order to understand its behavior under cyclic loadings. (2) The GSI system is then subjected to a series of shaking table tests with different levels of input ground shakings. (3) By varying the controlling parameters such as percentage of rubber in RSM, thickness of RSM layer, coupled with the weight of superstructure, a comprehensive parametric study is performed. This experimental survey demonstrates the excellent performance of the GSI system for potential seismic hazard mitigation.
Determination of Critical Distortional Buckling Load for Thin-Walled C Steel Section
Authors: Bao Chun Sheng , Han Xiao Bin , Wang Wei
Published: December 2010

The differential equations about distortional buckling are established according to the distortional buckling mode of cold-formed thin-walled C steel on the lateral and vertical loads. The formula of critical moment is obtained according to the differential equations of bending. This formula can calculate the critical moment if the properties of the section of C steel are given.
Seismic Performance on Dumbbell-Shape Connection between Steel Beams and Rectangular Concrete-Filled Tubular Column
Authors: Wang Xiu Li , Li Qiong
Published: December 2010

Referancing to the connection characteristic and mechanical behavior as well as the defects in application of joints on concrete-filled steel tube between columns and beams, a new connection type of steel beam throughout joints model is proposed. The inner force transfer mechanism and stress distribution situation of the joint under the monotonous load and hysteretic behavior, ductility, energy dissipation under cyclically lateral load are analyzed using the software ANSYS. The result indicated that the stress of steel pipe is reduced effectively when continious web plate joint is used. Meanwhile, the rigidity of the joint is enhancedand. It is also accord with the seismic design concepts, that is “strong column-weak beam“. During this process of the jiont working, plastic hinge occurs out of joint area on the beam. The hysteretic curves of all the specimens are of a plump shuttle shape .The curves don’t show strength deterioration and stiffness degradation obviously. All these show that this type of joint is effective.
Nonlinear Analysis on Reinforced Concrete Frame Joints under Thermal-Stress Coupling
Authors: Wang Yu Zhuo , Fu Chuan Guo
Published: December 2010

Based on ABAQUS finite element analysis, nonlinear analysis about mechanical performance of reinforced concrete beam-column joints under thermal-stress coupling is carried out. This paper mainly research the temperature field distribution, the beam deformation of frame joints under fire and the influence of different parameters such as the axial compression ratio, beam layer thickness, reinforcement ratio on fire resistance of frame joint. Conclusions was drawn as: forming temperature gradient from the outside to the inside in frame joint; displacement of the end of the beam suddenly increase after plastic hinge appearing, the sudden destruction contains contingency; Due to the damage began from plastic hinge at the end of the beam, the axial compression ratio has less influence about fire resistance of frame joint; The thicker of beam layer thickness, the longer of joint refractory limit; the higher of reinforcement ratio ,the later of plastic hinge 's formation, that is good for fire resistance.
Quantification Methods for Construction Waste Generation at Construction Sites: A Review
Authors: Masudi Ahmad Firman , Che Hassan Che Rosmani , Mahmood Noor Zalina , Mokhtar Siti Nazziera , Sulaiman Nik Meriam
Published: December 2010

Estimation of construction and demolition (C&D) waste amount is crucial for implementing waste minimization program. Estimation of C&D waste amount generated is a mean in assessing the potential for waste reduction. Thus, a better understanding of C&D waste generation in terms of causes and sources can be achieved. The aim of this paper is to conduct a review on available construction waste quantification methods from previous studies, which have been utilized in certain countries, while attempting to choose the most suitable and applicable method, and to direct future studies for better quantification methods. This review is applicable only for building construction projects and did not include civil/infrastructure, demolition, renovation, and excavation projects. Six quantification methods and/or waste audit tool available from literatures are discussed, which include their limitation and future direction for this study. It is believed that some combination of these quantification methods could make a good impact in accurate numerical estimation of construction waste amount generated in building construction projects. A strong and accurate database as presented by Soliz-Guzman, combined with effective, vital, and resourceful estimation suggested by Jalali’s Global Index (GI), also with the aid of user-friendly software tool like the SMARTAudit could provide an effective and reliable waste quantification.
The Analysis on how the Polypropylene Fiber Reinforced Concrete Works
Authors: Wang Shi Jie , Zhu Xun , Wang Wei , Li Jun
Published: December 2010

In this paper, we take the polypropylene fibers in concrete mechanisms as the starting point, then analysis the impact of the following four effects on the properties of polypropylene fiber concrete: thickening effect, toughening effect, crack resistance effect, load transfer effect, from which was out the following useful conclusions: the rate of low-doped fiber reinforced concrete with polypropylene fiber content increases, can further reduce the spacing between fibers in concrete to enhance crack resistance effect, the intrinsic quality of concrete with high resistance to dynamic load characteristics of sensitivity is also can be improved, and after the concrete has better crack toughness, with due extension of time to eliminate vibration molding concrete thickening effect on the strength of the adverse effects; incorporation activity of mixed materials.
The Simulation and Role of Discontinuous Yield Behaviors of Material
Authors: Hu Shao Wei
Published: December 2010

Discontinuous yield of material as Jerky flow was explained. Then, the strain rate sensitivity (SRS) and instability criterion was given out. Some tests were carried out at constant stress rate, so Jerky flow is manifested as a discontinuity in the stress-strain curves in form of strain bursts. Finally, the dynamic behaviors of specimens during instability of thermal origin were simulated with COLSYS software, whose results are good with test ones.
An Analytical Model of Stress-Transfer in the Nano-Composites with Debonding Interface
Authors: Zhu Wen Liang , Luo Dong Mei , Zhou Ying Long , Wang Wen Xue
Published: December 2010

An improved shear-lag analytical model has been established to study stress transfer in carbon nanotube (CNT) reinforced polymer matrix composites with and without debonding interface. The Poisson’s effect and radial effect of matrix is considered in the model for the first time, and a simplified 2D representative volume element (RVE) is modeled using a four-phase composite composed of matrix, nanotube, bonded, and debonded interfaces in this analysis, and the axial stress for CNT and matrix and interfacial shear stress along the CNT is predicted. The results show that load transfer efficiency in CNT reinforced composites is affected by the debonding length, and the abrupt change of shear stress is existent at the tip of debonding interface.
The Research on the Stress Concentration Factor of T-Joints Subjected to Axial Load
Authors: Zhang Jia , Qu Shu Ying , Zhang Guo Dong , Liu Hao
Published: December 2010

By terms of the numerical modeling of ABAQUS software, the analysis of the stress concentration factor (SCF) of tubular T-joints subjected to axial load is analyzed in this paper. The magnitude and the distribution of the SCF are also obtained. Through the finite element analysis of 816 models, the effect of geometrical parameters on the value and distribution of the SCF is investigated. Then based on these results, the parametric equations of the maximal SCF and SCF distribution for T-joints subjected to axial load are presented. Error analysis of these parametric equations is also carried out.
Study on the Cut-and-Fill Roadbed Reinforced by Triaxial Geogrid
Authors: Ma Qiang , Zheng Jun Jie , Zhang Jun
Published: December 2010

In order to treat the cut-and-fill embankment economically and effectively, geogrid was adopted to reinforce the filling body in cut-and-fill sections. After the discussion of causes of the pavement diseases and the mechanism of geogrid reinforcement, the triaxial geogrid was introduced with its special mechanical characters, and forces analysis of geogrid was carried out to establish a tension calculation model. Through the analysis, the theoretical calculation formula of geogrid tension was obtained, it could be used to calculate the tensile force of geogrid at the junction, which was also the required anchoring force for the geogrid at the anchorage point. Then, according to a typical embankment section in Chang-zhi to An-yang expressway, a finite element model was established to study the variation laws of tension of geogrid, lateral displacement and differential settlement of pavement. The results show that the triaxial geogrid reinforcement could reduce the differential settlement and lateral displacement of cut-and-fill embankment more economically and effectively than traditional geogrids.
Buckling Strength of Tapered Cylindrical Shells under Partial Axial Compression: Effect of Circumferential Weld-Induced Imperfections
Authors: Wang Zhen , Zhao Yang
Published: December 2010

Buckling is often the main design consideration for thin cylindrical shells. For most load cases, the stability behavior of the shell is acutely sensitive to circumferential weld-induced imperfections, and the corresponding residual stresses are some beneficial to buckling strength of the shell generally. However, these conclusions are all based on the cylinders with constant wall thickness, and the studies about the effect of residual stresses on buckling strength of tapered cylindrical shells under partial axial compression are few. This paper applies trapezoidal strain field approach to simulate circumferential weld-induced imperfections on tapered cylindrical shellls, and studies the stability behavior of the cylinders with single circumferential weld and multiple circumferential welds under partial axial compression respectively. By comparing the results derived from the models with/without circumferential welds and corresponding residual stresses, the effects of weld depressions and residual stresses on tapered cylindrical shells under partial axial compression are obtained.
Distortional Buckling of Cold-Formed Thin-Walled Channel Beams in Combined Compression and Minor Axis Bending
Authors: Luo Hong Guang , Guo Yao Jie , Xu Yun
Published: December 2010

On the basis of the Generalized Beam Theory (GBT), this paper presents an elastic analysis of the distortional critical stress of cold-formed thin-walled lipped channels in combined compression and minor axis bending. The results obtained using the exact analysis presented herein have shown excellent agreement with previous available results. And the accuracy, validity and effectiveness of the presented solution were demonstrated. The calculating process was displayed by an example which can give reference to the research and design. This paper will contribute to the understanding of distortional mechanics in thin-walled members.
Study on Mechanical Properties of the Long Span Cable-Stayed Bridge with Three Main Trusses and Three Cable Planes
Authors: Zheng Peng Fei , Dai Gong Lian , Li Di Ping
Published: December 2010

Tianxingzhou cable-stayed bridge firstly adopts the innovative structure which is composed of three main trusses and three cable planes, and its mechanical properties are different from those of the traditional structure with double main trusses and double main planes. In this paper, based on the study about the cable tension distributed properties of the completed bridge with three cable planes, and through comparing analysis on the bridge with three main trusses and that with double main trusses, the mechanical properties of the bridge with three main trusses and three main planes were investigated. In the end, the calculated results show as follows: cable tension distributes well after rational optimal calculation. Although there will be more construction works for the added cable plane, per cable tension reduces, and it makes the anchor zone with simpler structure and cable replacing more conveniently; Under same level stress, the three-main-truss structure has smaller component, which makes construction more conveniently; The three-main-truss structure has a lower torsional stiffness, but it can be effectively improved by enhancing axial rigidity of lateral bracing; Under the condition of the same materials, the bridge with three main trusses has lower stress. Therefore, the cable-stayed bridge with three main trusses and three main planes is the rational choice for multi-line railway and rail-cum-road bridges.
Study on Preparation and Performance of Radiation Shielding Aggregate Made from Sludge with High Content of Barium
Authors: Huang Xiu Lin , Sun Hua , Ding Qing Jun , Han Ji Yu
Published: December 2010

Aggregate is the main contribution to shield the radiation in the radiation shielding concrete. Based on the fact that the heavy element barium has excellent γ-rays shielding function, sludge with the high content of barium has been made into aggregate with low dissolution rate and high strength by calcination at high temperature; the existing forms of element barium after it was melted inside the aggregate have been analyzed by using XRD and SEM techniques; the linear attenuation coefficients have been measured among the functional aggregates, basalt and barite. The results have showed that the radiation shielding capacity of functional aggregate has been improved substantially compared with the basalt, however, it is equal to barite.
Static Analysis of Friction Contact Effect on Valley Cable Force
Authors: Zhang Yang , Zhang Yi Gang , Xiang Yang
Published: December 2010

In order to study the friction contact effect between cable and membrane in cable-membrane structures, a tensioned cable-membrane FE model which has a stable cable (valley cable) is created with FEA software ANSYS. The friction contact between the valley cable and membrane surface is simulated by contact elements in ANSYS, and the effect of friction contact surface is considered by the introduction of friction coefficients. Three different design valley cable forces (15kN, 20kN and 25kN) are considered in form-finding and static analysis, and valley cable force losses are analyzed. Results show that valley cable force loss due to friction contact should be considered obviously when design valley cable force is relatively small.
Simulation Method on Progressive Collapse of Shell Model under Severe Earthquake
Authors: Zhou Hai Tao , Zhang Yi Gang , Yang Da Bin , Wu Jin Zhi
Published: December 2010

To analysis progressive collapse behavior of single-layer reticulated shell under severe earthquake, based on spatial fiber beam element failure criteria, a simulation method on progressive collapse of shell is presented, which account of mechanical properties of components after buckling and damage accumulation effect of combine hardening material. And a computation program is developed correspondingly. At last the method and program proves to be applicable by an example.
Design and Stability Analysis for an Arch-Shell Hybrid Structure, Singapore Cool Dry Conservatory
Authors: Bai Yin , Wang Yuan Qing , Shi Yong Jiu
Published: December 2010

Singapore Cool Dry conservatory is a huge space steel structure which is for exhibiting plants suited for living in cool and dry conditions. Due to its seashell shape, it adopts arch-shell hybrid structural system. Double-layer glass curtain walls are suspended to the shell, while cables are tensioned between large arches to increase lateral stability capacity. Because of this structure’s specialty, traditional structural design software in China can not meet the need. FEA software ANSYS was employed to make design optimization, and make further verification. The global stability bearing capacities considering geometry non-linear elasticity and elasto-plasticity conditions were evacuated and analyzed.
The Design Review and Optimization of the Special-Shaped Steel Frame Structure
Authors: Tang Ke Dong , Fu Jian , Dai Jun , Zhang Peng , Yu Rui Feng
Published: December 2010

According to the finite element analysis of a circulating fluidized bed boiler steel frame structure, the essay concludes to the calculation results of the main steel structure, moreover the structure and the composition of bars are adjusted and optimized which improve the safety of the structure reliability and reduce the volume of steel. All of the above contents have certain reference value on the similar structure.
Effects of Rare Earths on Austenite Grain Growth Behavior in X80 Pipeline Steel
Authors: Liu Cheng Jun , Liu Hong Liang , Jiang Mao Fa
Published: December 2010

Accorded with the criteria the X80 pipeline steels with RE additions have been prepared with a vacuum induction furnace. The effect of rare earths (RE) on austenite grain growth behavior in pipeline steel has been discussed in this work. After hot rolled, the effect of RE on austenite grain growth behavior have been studied by the thermal simulator, scanning electron microscopy and metallographic microscope. The results indicate that RE additions inhibit the abnormal growth of austenite grain, trace RE could significantly influence the austenite grain growth behavior, and obtain fine grain size in X80 pipeline steel. For instance, the activation energy of grain growth reduced from 475 kJ/mol to 425 kJ/mol with addition of 0.0220 wt.% RE according with no deliberate RE additions, but the grain growth index increased from 3.5 to 4.5.
Study on Mechanical Behavior of Concrete-Filled Square Tubular Column and Bolt-Weld Steel Beam Joints with Reduced Beam Section
Authors: Nie Shao Feng , Zhou Tian Hua , Liu Xiang Bin , Wang Xiu Mei
Published: December 2010

The nonlinear FEM models of concrete-filled square tubular column with internal diaphragms and steel beams with reduced beam section bolt-weld joints, involving geometric, materials and contact nonlinear, were established. The 3D models of beam-to-column joints with internal diaphragms by 3D solid elements are founded. The bearing capacity behavior of joints under the monotonic loading are analyzed, including P-Δ curves, the stresses distribution of beam, the dissipating energy ability and destruction form. The analysis results show that the initial stiffness of joint with reduced beam section is close to that of non-reduced beam section joint. The bearing capacities of joints with reduced beam section are lower a little than that of non-reduced beam section joint. The plastic hinge in the joint with reduced beam section is removed to the reduced beam region.
Study on Structural Rigidity of Large Span Three-Tower Cable-Stayed Bridge on High-Speed Railway
Authors: Yi Lun Xiong , Zhang Ye Zhi , Zhou De
Published: December 2010

Based on Dongting Hu three-tower cable-stayed bridge on high-speed railway, stiffness ratio of middle tower to side tower (SROMTTST), vertical bending resistance stiffness (VBRS) of girder, height of tower, area of cable were studied by using FEM. The results show that the structure is more economical on condition of the SROMTTST less than 3.0. With the increase of VBRS of girder, the tensile forces of the cables near mid span increase and decrease near towers. Meanwhile, both the moments of the tower and the deflection of the girder get smaller. The ratio of tower height to span (ROTHTS) has great influence on the bridge rigidity. Every 0.01 increase of the ROTHTS can decrease a ratio of deflection to span (RODTS) about by 3%～5%.
Experimental Study on Mechanical Behavior of Cold-Formed Steel Three Limbs Built-up Section Members
Authors: Zhou Tian Hua , Nie Shao Feng , Liu Xiang Bin , Li Guang Yi
Published: December 2010

18 specimens of cold-formed steel three limbs built-up section members are tested under axial compression load in this paper. The section forms are divided into two categories: A and B. Load-displacement (P-Δ) curves and failure characteristics of specimens are obtained. The results show that: As to section A members, the failure characteristics of LC, MC and SC series of specimens are flexural-torsional buckling, torsional buckling and distortional buckling, local buckling and distortional buckling. As to section B members, the failure characteristics of LC, MC series of specimens are flexural buckling, while local buckling and distortional buckling for members of SC series.
Analysis on the Mechanical Properties of Connections on Cold-Formed Square Steel Column and Beam
Authors: Yao Yong , Chu Yun Peng
Published: December 2010

The profiled steel structure of cold-formed square steel tubular has better seismic behavior and is suitable for reconstruction in seismic disastrous area. The joint is the key to the design of structure, so it needs further research on the mechanical properties. Using finite element software ANSYS to analysis two kinds of welding joints which under monotonic loading, the results show that: (1)The ultimate bearing capacity and yield load of improved joints greatly enhanced compared to conventional joints, and the plastic hinge moved to outward from the beam and column interface. (2)Until loading to the yield load, the improved joints has longer yield platform and better ductility. (3)The axial compression ratio has stronger effect on the conventional joints than improved joints on bearing capacity and initial stiffness.(4)Until loading to the ultimate load, degree of stress concentration on the improved joints is less than conventional joints, and the plastic hinge moved to outward, avoid brittle fracture of the joint.
Mechanical Model Study of a Bolted Endplate Minor Axis Joint
Authors: Wang Zhi Yu , Wang Qing Yuan
Published: December 2010

An analysis of a bolted endplate minor axis joint that is subjected to bending is presented in this paper. The methodology for predicting the moment-rotation relationship of such joint is based on the component method and appropriate mathematical expressions. The component of column web in bending is of special concern, by using yield line analysis and plate theory, for calculation of the resistance and the stiffness respectively. A case study is reported in this work to validate the proposed mechanical model. The result is found to be satisfactory for the prediction of moment-rotation relationship, and the validity of the proposed model is discussed.
Experimental Study of Post-Fire Bearing Capacity of the Circular Steel Tubes with Different Fire-Resistant Coating
Authors: Ji Yao , Wang Xin Tang , Zhou Ming , Wang Wan Zhen
Published: December 2010

In order to look into the causes of fire response and post-fire bearing capacity of the steel tubular columns protected with different materials, the fire test was conducted for a set of circular steel tubes protected with different materials such as gypsum fireproof panel, bamboo plywood and the ordinary lumber core plywood, and the steel tube without any protective material. The fire response temperature of surface of steel tubes is measured and the axial compressive bearing capacity of the specimens after fire are tested and analyzed. The test results show that gypsum fireproof panel has the best fire protection characteristics, the ordinary lumber core plywood and bamboo plywood can also retard rising of the surface temperature of the steel tubes during the initial 35min although they are combustible materials. It is found that the post-fire bearing capacity of the steel tubes protected with different materials varies evidently, and the maximum value of response temperature has the greatest effect.
Shrinkage and Cracking of Cement Composites Containing Internal Curing Stuff
Authors: Li Xue Ying , Zhao Ya Ding , Ma Xin Wei
Published: December 2010

The influence of superabsorbent polymers (SAP) as internal curing stuff on the restrained shrinkage and cracking of concrete was investigated. Results show that SAP in the mortar with slag and silica fume increases the compressive train of the steel ring, but postpones the initial cracking time of the mortar from 5 days to 6.5 days and reduces the crack width by 25% at age of 28 days.
Sensitivity Analysis of Manufacture Errors for Cable Dome
Authors: Zhang Jian Hua , Wang Zhen Qing , Zhang Yi Gang
Published: December 2010

Construction control is the key technique for cable dome. During the actual engineering, however, it is difficult to ensure no difference between the real prestress distribution and the designed value due to existed construction errors. The practical problem for cable dome construction is to determine how much is allowable errors limit. To solve the problem, sensitivity analysis of manufacture errors of bearing and cable length are carried out in this paper. The random errors are simulated by Monte Carlo method. In a numerical model of cable dome with the diameter of 62m, the sensitivity of effect of bearing and cable length manufacture errors on structural performance is analyzed. Numerical results show that the manufacture errors of radial bearing, hoop cable 2, ridge cable 3, diagonal cable 3 and hoop cable 1 should be strictly controlled. Besides, the maximum allowable errors are proposed referring to the domestic existing specifications.
Parameteric Study of Castellated Beam
Authors: Pachpor P.D. , Gupta L.M. , Deshpande N.V. , Bedi Komal
Published: December 2010

“Castellated beam” is a name commonly used for type of expanded beam. Castellated beams combine beauty, versatility, economy in steel design. These are fabricated from standard rolled section and are engineered to save time of construction, enabling saving in steel and reducing building costs. These are mainly designed to reduce weight and at the same time increase the efficiency in structural performance. The principal advantage of castellation is the increase in vertical bending stiffness castellated beams have proved to be efficient for moderately loaded longer spans where the Design is controlled by moment capacity or deflection. In this paper a steel beam is selected and Finite Element Analysis is done for constant loading and support condition by using ANSYS software. The deflection pattern at the center of castellated beam is studied for different parametric conditions by changing depth of hexagon to the depth of web ratio and also by changing the position of hexagon along the length of the beam. A comparison is done for various conditions.
Influence of Segmented Construction Methods on the Prestressed State of Truss String Structure Roof of Xinjiang Exhibition Center
Authors: Zhang Jin , Luo Xin Chang , Cai Jian Guo , Feng Jian , Yang Xiao Jing
Published: December 2010

Taking Xinjiang Exhibition Center Roof as an example, three models ("No construction stage" model, "Stretching on the ground" model and "Flow construction stage" model) were set up and analyzed with consideration of different segmented construction methods. The results show that the effect of the segmented construction method on the prestressed state of long-span truss string structures is significant. For the "No construction stage" model, the maximal cable force during construction is the largest among three models, while there are great differences between each cable force. However, the maximal displacement of sliding ends is the smallest among three models. For the "Stretching on the ground" model, the tension control force is the most uniform. This is because the cable of every truss is pre-tensioned independently, which causes no influence on other cables. For the "Flow construction stage" model, the maximal displacement of sliding ends and the uniformity of cable forces of the truss string structures are between those given by the other two models.
Numerical Analysis of Prestressed Steel Box Beams
Authors: Jia Yan Min , Liang Dong Wei
Published: December 2010

The prestressed steel beam is regarded as a composite system of beam and cables, and the interaction of the two parts is fully considered. The variational method is used to derive the equations for calculating the tension increment of external cables and deflection of steel beam under applied loadings. A model test of prestressed steel beam is used to verify the calculation results.
Property Research of Carbon Fiber Reinforced High Performance Concrete Containing Limestone Powder
Authors: Li Hong Fang , Yun Ying Wei , Jang Ii Young , Kim Seong Kyum
Published: December 2010

In this paper, the properties of CF (carbon fiber) reinforced HPC (high performance concrete) containing LP (limestone powder) have been studied including its compressive strength, flexural strength, chloride ion permeation resistance, wearability and acid rain resistance. The results show that flexural strength, acid rain resistance and wearability of CF reinforced HPC containing LP are all better than those of LP HPC without CF, moreover, its flexural strength at 7days and 28days are both larger than 10MPa. While the short-term compressive strength and resistance to chloride ion permeation are decreased by introducing CF. Also the results indicate that CF reinforced HPC containing LP suits to be used as road pavement materials in abundant acid rain area.