bluuebunny/crossref_metadata_2025 huggingface dataset:
Defect Monitoring of CFRP with Ultrasonic C-Scan Method
Authors: Li Peng , Gao Xiao Jin , Luo Yan , Kong Huan Ping , Zhao Zi Hua , Zhang Zheng
Published: May 2011

In this study, carbon fiber reinforced polymer (CFRP) laminates that were under three-point bending load within and without initial impact damage, were detected and monitored by ultrasonic C-scan method. The defect morphology at various load levels was recorded. The dynamic monitoring for the growth of delaminations in CFRP laminates was acquired, and it provided an experimental evidence for the health monitoring on CFRP in service.
Monitoring Dynamic Characteristics for a Supertall Structure under Different Loading Events
Authors: Chen W.H , Lu Z.R. , Chen S.H. , Ni Y.Q. , Liao W.Y.
Published: May 2011

The Guangzhou New TV Tower (GNTVT), completed its construction in May 2009 in Guangzhou China, is a super tall tube-in-tube structure with a total height of 600m. A complicated structural health monitoring (SHM) system consisting of over 700 sensors has been implemented to the GNTVT for both in-construction and in-service real-time monitoring. This implemented SHM system has monitored the structural responses of the GNTVT after having completed its construction under different loading events (the typhoon, the earthquake and normal wind loading conditions). Firstly, the time history and PSD of the acceleration response under different loading events have been compared. Secondly, the modal properties (modal frequencies, mode shapes, and damping ratios) of the structure under different loading events have been identified. The results of this paper supply some references for better understanding the dynamic characteristics of supertall under different loadings.
Research on the Seismic Response Characteristic under Different Curvature Radios
Authors: Li Qing Ning , Jiang Feng Jie , Wang Tian Li , Sun Jian Pen , Wang Lei Juan
Published: May 2011

The curvature radius is a very important factor which influences the dynamic performance of the curved continuous long bridge badly. This paper based on the practical engineering, with large finite element program, established the curved continuous long bridge space finite element calculation model. Respectively by response spectrum method and the time-history response method, consider single-point excitation and multi-support excitation seismic action, Analyzes different radius of curvature in curved continuous long bridge self-vibration frequency, internal force and displacement on the differences, and given the internal relations between the difference and the curvature radius, offer some reasonable design reference suggestion for curved continuous long bridge of the radius of curvature.
Random Decrement Technique Based on the Sampling Methods
Authors: Zhang Chuan Xiong , Shi Wen Hai , Li Zheng Nong
Published: May 2011

This paper presents the random decrement (RD) technique based on the sampling method for parameter identification of linear dynamic system. The development of RD technique was elaborated briefly in the aspects of identifying the dynamic properties, and then this paper summarized the corresponding parameters recognition problems due to the quantity and quality of measured sampling segments. Detailed analysis of two kinds of sampling method (the probability-proportional-to-size and two-stage sampling) is conducted to investigate its adaptation range in extracting RD signatures. The results of two simulated examples indicates that in view of the different vibration parameter recognition situation, the above provided RD technique based on different sampling methods could improve the quality of RD signature obviously, and lead to a quite accurate frequency and the damping ratio of structural system under the effective use of all measured sampling segments.
Application of FBG Sensor in Shaft Structural Deformation Monitoring of JINCHUAN Mine No.3
Authors: Liu Zeng Hui , Gao Qian , Yang Zhi Qiang
Published: May 2011

In order to effectively evaluate the security status of shaft and to make timely and accurate forecasts before the shaft break disaster, lead into fiber brag grating technology in the mine shaft deformation monitoring. Designing laboratory experiments verified FBG sensing the reliability of deformation and strain transfer law in reinforced concrete beams, while provide practical experience to the FBG sensors installed on the actual shaft structure. According to the structural condition of the main shaft of JINCHUAN Mine No.3, designed 8 monitoring sections in different level ingate upper and lower and installed fiber optic grating sensors, forming a fully automatic real-time and long-term deformation monitoring system. Initial monitoring results indicate that only the No.4 (down) sensors was failure, but the other seven monitoring sections can effectively detect the corresponding strain, and the monitoring system was stable. The fiber optical sensing technology has broad application prospects in the state's long-term monitoring deformation of the mine project, for the mine shaft deformation monitoring provides a more reliable monitoring method.
Vibration Monitoring and Safety Evaluation of Blasting at an Underground Engineering
Authors: Yin Zhi Zheng
Published: May 2011

In this paper, the blast vibration was monitored and the data from an underground engineering were analyzed. The empirical formula of the relation between the maximum vertical direction vibration velocity and the scaled explosive charge, the maximum horizontal radius direction vibration velocity and the scaled explosive charge, the maximum horizontal tangential direction vibration velocity and the scaled explosive charge were determined. According to the blasting safety regulations, the safety standard of the blasting vibration velocity is less than 7.0 cm/s. Through monitoring and inspection, the safety evaluation of the secondary lining of the highway tunnel was made. The safety evaluation of the protected highway tunnel is safety under the blasting vibration.
HHT-Based Modal Parameter Identification of Time-Varying Structures and Experiment Study
Authors: Wang Xue Min , Huang Fang Lin
Published: May 2011

A method for modal parameter identification of time-varying structures based on Hilbert- Huang transform (HHT) is presented. Theoretical formulas for identifying the modal frequency and damping radio using the displacement response of a time-varying SDOF structure are deduced. Taking advantage of modal filtering characteristics of empirical mode decomposition (EMD), the presented method is expanded to identify the modal parameters of MDOF structures. Numerical simulation of a three degrees of freedom structure with time-varying stiffness and damping show the validity of the method. Finally, a time-varying structure experiment is designed to further study the method. The experimental device is a cantilever beam. By adjusting the adjunctive mass and stiffness, two kinds of time-varying structures with continuous mass change and stiffness change is realized respectively. Modal parameters are identified from the free acceleration response of the beam.
Study on the Deformation Characteristics of Supporting System of Deep Foundation Pit in Subway Station Construction
Authors: Zhang Hua Zhi , Feng Yi Fang
Published: May 2011

Taking Jiyu Bridge Station of Wuhan Metro Project as example, the deformation characteristics of supporting system of deep foundation pit was studied by means of numerical simulation (FLAC3D) in consideration of construction order. The deformation fields of different excavation depths of diaphram wall were obtained and analyzed in order to gain the maximum horizontal displacement value and settlement value. By comparison with the monitoring data, the simulation results can basically reflect the deformation characteristics. Moreover, the simulation results showed that the application of diaphram wall was feasible for foundation pit supporting in Jiyu Bridge Station, meanwhile, the results can be based on to guide the construction.
Study on Strength Estimating of Recycled Concrete Based on Rebound Method and Ultrasonic-Rebound Combined Method
Authors: Chen Jun , Su You Wen , Lei Ting , Gu Song
Published: May 2011

In order to test the applicability of the strength curves of rebound method and ultrasonic-rebound combined method of common concrete in estimating the strength of recycled concrete, basis on the C30 recycled concrete specimens with 70% of recycled coarse aggregate replacement are designed, then changing the replacement ratio of recycled coarse aggregate for experimental verification. The results show that It will lead to a large error if using the strength curves of common concrete to estimate the strength of recycled concrete, and the error grows with the growth of the replacement ratio of recycled coarse aggregate. So It is necessary to establish the special purpose strength curves of recycled concrete with the rate of recycled coarse aggregate. Finally, the strength curves of recycled concrete with recycled coarse aggregate are 30%,50%,70% and 100% are given in this test conditions in this paper.
Designing and Construction of Monolithic Moving for an Office Building
Authors: Zhao Shi Yong , Wang Tie Cheng
Published: May 2011

Monolithic moving of the buildings has supplied a new choice for the urban planning and reforming. The paper studied the designing and construction of monolithic moving for a four-story frame structure building, and introduced a series of calculating methods and construction technology, including the arrangement of the track beam，the calculation of the underpinning joint, the calculation and selection of the underpinning system，the selection and arrangement of the rolling device, the construction controls of moving, and the connecting of the new foundation.
Simulation Analysis on Repair of Concrete Beams Using Near-Surface Mounted GFRP Bars
Authors: Zhang Hai Xia , Liu Guo Rui , Cao Peng Peng
Published: May 2011

This paper focuses on the characterization of flexural behavior of RC beams strengthened with Near-Surface Mounted (NSM) GFRP bars. Based on ABAQUS, the finite element model for the flexural behavior is established and the simulated results are compared with the test results. The parameters including the amount of GFRP bars, the embedment length of GFRP bars, the types of FRP bars, and the ratio of internal steel reinforcement in the beam for the flexural behavior are discussed. The simulated results show that there has a good agreement with the experiment results. The beams strengthened with NSM GFRP bars have a significant improvement in flexural stiffness and bending capacity. Further more, the analysis results on the parameters indicate that ultimate bearing capacity of the beam strengthened with NSM-GFRP bars gradually increases with the amount of FRP bars and the ratio of the longitudinal steel reinforcement. The mode of failure of the beam strengthened with the smaller embedment length of GFRP bars is not the rupture of GFRP bars. The different types of FRP bars have a great influence on the load-deflection curves of the beams.
Performance Analysis of Concrete Silo Structure Strengthened with Carbon Fiber Reinforced Polymer Laminate
Authors: Ding Yong Gang , Wang Jian Qiang , Wang Xi Zhu , Feng Wen Tao
Published: May 2011

Due to the low design standards when constructed, limited construction materials, corrosion damage from natural environments and degeneration in normal use process, some reinforced concrete silos put up in the 1980s and 1990s are facing the troubles like decrease of bearing capacity, cracks and component damages, which are seriously affecting their normal use and bring certain security risks. Thus, the strengthening of these silos should be taken into account. In this paper, the positions that should be paid more attention when strengthened are obtained through finite element method analysis of a silo. Then the silo is strengthened with carbon fiber sheet through three different reinforcement conditions. The structure performances after being strengthened are analyzed, and the factors that affect the reinforcement effects are summarized.
Experimental Study on Hysteretic Behavior of the Concrete Filled Circular CFRP-Steel Tubular (C-CFRP-CFST) Beam-Columns
Authors: Wang Qing Li , Che Yuan , Shao Yong Bo , Wu Jun
Published: May 2011

Overall 12 specimens were experimentally investigated in this paper to study the hysteretic behaviors of the concrete-filled circular CFRP-steel tubular (C-CFRP-CFST) beam-columns. The test results indicated that CFRP can provide transverse confinement effect and longitudinal strengthening effect for the concrete filled circular steel tubular (C-CFST) beam-columns effectively and the local buckling of the steel tube is deferred. With the increase of the strengthening factor of the longitudinal CFRP, the damage scale reduces.
Design Method of Reinforced Concrete Beams Strengthened with Prestressed CFRP Plates Base on Ductility
Authors: Deng Lang Ni , Zhang Jun , Chen Hua , Zhang Peng
Published: May 2011

For reinforced concrete beams strengthened with prestressed carbon fiber reinforced polymer (CFRP) plates, design methods are derived for determining the allowable plate area or initial tension control stress of CFRP plate to achieve a targeted value of ductility. The derivation of equilibrium and compatibility equations for a rectangular cross section is presented. Base on the test of 2 reinforced concrete beams strengthened with prestressed CFRP plates, analytical results are compared with experimental results. Comparisons show that the design methods have good applicability. It can provide a reference for engineering application of strengthening design.
The Settlement Analysis and Reinforcement of a Cast-In Situ Concrete Floor
Authors: Zhao Hua Wei , Zhu Hong Ping , Ding Ya Hong
Published: May 2011

After form a removal concrete cross ribbed beam floor in a commercial plaza, the vertical cracks are discovered, and the settlement analysis and reinforcement of a Cast-in-situ concrete floor are performed. The detection of the maximum crack is 0.3mm,and the Maximum settlement of cross ribbed beam is 48mm. By theoretical analysis, improper form removal during construction stage makes the actual floor force inconsistent with the design of a load transfer, which is the main reason of the excessive settlement in the cross ribbed beam. Through the economy, ease of handling in construction and other aspects of comparative analyses, the close beam side by epoxy grout and paste the carbon fiber under the beam to reinforce the cross ribbed beam. After reinforcement, no defect is discovered in the project so far.
Rehabilitation of Concrete Beam by Using Martensitic Shape Memory Alloy Strands
Authors: Cui Di , Ping Guan
Published: May 2011

The rehabilitation properties of intelligent concrete beam reinforced with shape memory alloys (SMA) is investigated. In this study, SMA strands, made of 7 single wires, are used to replace the steel bars in ordinary concrete beam. The test of single point loading at the mid-span is conducted on the beam. The experiment has three stages including loading, unloading and heating the SMA strands. During heating the SMA strands by electrical current, the crack width can be reduced by taking the advantage of the shape memory effect of SMA strands. The results illustrate that SMA is a candidate material for rehabilitation of reinforced concrete structures.
Effect of Electrochemical Chloride Extraction on the Bond Performance between Steel Bar and Concrete
Authors: Guo Yu Xia , Gong Jing Xing
Published: May 2011

Based on beam specimens of 100mm×100mm×400mm, the effect of electrochemical chloride extraction (ECE) on bond performance between steel bar and concrete contaminated by chloride was studied by determining the bond strength of them. During the test, 1%, 2% and 3% NaCl by weight of cement were mixed into concrete to simulate chloride contamination. In the process of ECE, four kinds of current density (1, 2, 3, 5 A/m2of steel bar area) and electric quantity (500, 1000, 1500 and 3000 A.h/m2of steel bar area) were taken into account, respectively. It is indicated that the bond strength between steel bar and concrete was degraded after ECE treatment, the more the current and the electric quantity of ECE are, the more the loss of bond strength is, and the initial content of chloride in concrete has a little influence on the bond strength.
Exploration on the Underpinning Technology of One Masonry Structure
Authors: Lv Heng Lin , Xu Chun Hua , Zhou Shu Chun , Zhu Yue Xing , Ding Shi Jie
Published: May 2011

Because of the change of using function of one masonry structure, its longitudinal walls need to be underpinned. The related members also need to be reinforced. This paper has a discussion on the thought of underpinning part, strengthening method and key construction process. They main involve the reinforcement of foundation, the transformation from non-bearing members to bearing members of ring beams and constructional columns. It also involves the construction points for attention during underpinning process. At last, the main points that shuold be paid attention to in strengthening deign and underpinning construction are concluded.
Numerical Simulation Procedure of RC Beam Reinforcement with FRP
Authors: Fu Chao Jiang
Published: May 2011

The use of fiber reinforced polymers (FRP) to reinforce reinforced concrete(RC) structure has become one of the main applications of composites in civil engineering. FRP composite is analyzed using the serial/parallel mixing theory, which deduces the composite behavior from the constitutive equations of its components. Numerical procedure of RC beam reinforceed with FRP is studied based on the finite element method. The numerical results accord with the test results. The validity of the proposed procedure is proved comparing numerical and experimental results.
Experimental Study on Shear Behavior of RC Beams Strengthened with Stainless Steel Wire Mesh
Authors: Liu Ming , Huang Hua , Hou Jian Ling , Liu Bo Quan
Published: May 2011

Rehabilitation of RC members with stainless steel wire mesh and permeability polymer mortar is a new method of structural strengthening with the advantages of resistance to fire, corrosion and ageing. Experiments were conducted to investigate the shear behavior of eight strengthened RC rectangular beams and one comparative RC beam. The shear mechanism of strengthened beams was analyzed, and the influences of the strengthening manners, bolts’ amount, bolts’ distance on the shear behavior of strengthened beams were discussed. The test results show that the rehabilitation greatly increase the beam’s shear load-carrying capacity, shear stiffness, and its ductility. But the range of load capacity improvement is greatly influenced by the bolts’ amount and distance, too much and dense bolts badly weaken the shear behavior of beam itself. The influences of the strengthening manners on the load capacity are puny, but the beams’ failure modes are different.
Simulation Calculation Analysis of RC Beam Strengthened with Carbon-Fiber by Reverse-Arch Method
Authors: Chen Dai Guo , Yao Yong , Deng Yong Jun
Published: May 2011

Using utilities equipment to make the reinforced concrete girder to generate a kind of reverse-arch radian, then paste CFRP on the under-part of the girder, after the CFRP was maintained, unload, at this time, the CFRP is working together with the primary reinforced concrete girder. Using analysis software ANSYS to simulate this process, comparing with the RC beam strengthened with carbon-fiber directed, a conclusion was got that is the deflection of a RC beam strengthened with carbon-fiber by reverse-arch method is much smaller and the CFRP to bear much loads than the ordinary method. The conclusion can be a reference to the similar projects.
Experimental Study of Flexural Capacity on RC Beams Strengthened with the FRP-Bolt Strengthening Technology
Authors: Guan Yan Hua , Zhuang Pei Zhi , Song Xiu Guang , Ma Zheng
Published: May 2011

On the basis of the destructive characteristics of aging RC beam bridges, experiments are conducted to examine and compare the effect on RC beams strengthened with FRP surface adhesion (EB-FRP) and FRP-bolt hybrid boding (HB-FRP). In particular, the influence of pre-cracking level on RC beams strengthened with the hybrid bonding of FRP is assessed. The experiment results show that the hybrid bonding of FRP is a more reliable strengthening technique which can improve the Flexural capacity of beams. The new bolt-fastening technique does not rely on bearing to transmit the interfacial shear, but increases the interfacial bond by resisting the separation of the FRP laminate from the concrete substrate by the bolt pretension instead. This study contributes to direct the design and the construction of HB-FRP.
Non-Probabilistic Slope Stability Analysis
Authors: Liu Chun Yuan , Zhang Jun Qi , Pan Gong , Song Hai Chao , Liu Cheng Wei
Published: May 2011

A high filled subgrade of a highway slipped on the left of the line. According to conventional calculations (limit equilibrium method) ,we can know that the safety factor K = 1.55 and the probability of reliability index β = 3.1, failure probability Pf = 0.001. Through the introduction of interval analysis theory, non-probabilistic reliability calculation model is established, and the non-probabilistic reliability index is η = 0.7. Showing that the non-probabilistic reliability theory in the absence of adequate data distribution of information and possible subjective assumptions can also obtain more accurate results.
Fuzzy AHP Comprehensive Approach-Based Damage Evaluation of Reinforced Concrete Frame Structure
Authors: Zheng Shan Suo , Li Zhi Qiang , Tao Qing Lin , Hu Yi , Hou Pi Ji
Published: May 2011

Fuzzy techniques and AHP approach have been widely used during the last decade. However, few papers have attempted to use the AHP approach that incorporates fuzzy techniques to evaluate the damage of framework. This paper, therefore, aims to set up a hierarchy structure of the damage and then develop a fuzzy analysis of framework for the damage evaluation of framework. In the process of damage evaluation, setting up the hierarchy structure, determining the weight vector by the AHP, setting up the fuzzy evaluation matrix and developing fuzzy AHP evaluation are detailed according to framework. Finally, 5-story framework is used to execute the proposed fuzzy AHP model. It is concluded that the results is effective and accurate.
The Research on Time-Dependent Reliability Analysis for RC Structures Based on the Theory of Stochastic Processes
Authors: Xia Cheng Yu , Liu Qing You , Qian Li Qin
Published: May 2011

This paper proposes a new calculating method for the reliability analysis of the time-varying structure，and applies the calculating method to optimize the design for the concrete structure . The RC compression member was taken as an example in the specific analysis in by the mean of resistance and structural reliability with time t. The results show that, this mode has a strong ability of analyzing adequately all kinds of random variant in procedure of structure failures.
Studies on Strain Fatigue Crack Growth Rate Controlled by Displacement or Load of 16MnR Steel
Authors: Yan Yan , Liu An Zhong , Zhou Dao Xiang
Published: May 2011

In order to understand the strain fatigue crack growth rate of pressure vessel steel controlled by displacement or load, we did experiments on strain fatigue of 16MnR steel and describe the fatigue with the energy method. We have obtained delayed cycle curve of strain fatigue controlled by displacement or load and calculated the J-integral at crack tip. In order to compare strain fatigue crack growth rates of 16MnR steel on two conditions，we compute weighted means of the strain fatigue controlled by displacement or load. Comparing two kinds of fatigue growth rate, it is obvious that the crack growth rate of fatigue controlled by displacement is greater than that controlled by load. All experiments show that compress plastic energy is higher, the fatigue growth rate of 16MnR is lower.
The Corrected Method of Strength Design of Plain Bolt Group Joints under Combined Load of Transverse Force and Torque
Authors: Han Ze Guang , Hao Rui Qin , Yang Ming Kun
Published: May 2011

In this paper, a corrected method about the strength design of plain bolt group connection under combined load of transverse force and torque has been proposed based on the shortage of existing literatures, and its universal strength expression has also been derived. The results of examples show that the method is general application under all layout of plain bolt group, and is further rich in the design methods of bolt group. It can also provide favorable help for designers.
Effectiveness of UHTCC to Retard Cover Expansive Cracking Due to Corrosion of Rebar in RC Structure
Authors: Cai Xin Hua , He Zhen , Xu Shi Lang
Published: May 2011

Ultra high toughness cementitious composite (UHTCC) shows a unique characteristic of limit the crack width with multiple fine cracks whether it is subjected to tensile load or bending load. The failure pattern of UHTCC exhibits saturated multiple fine cracks, so the durability of structures will be improved markedly by utilizing UHTCC partly or entirely instead of concrete. In this study, considering the tensile strain capacity of UHTCC, a formula for calculating the critical rebar corrosion ratio when the UHTCC cover cracking due to rebar corrosion through the theory of plasticity and cylindrical cavity expansion theory. The effectiveness of UHTCC for restraining the cover cracking due to rebar corrosion has been proved by a calculated example. The influences on critical rebar corrosion when the UHTCC cover cracking due to rebar corrosion have been analyzed. The analytical results showed that UHTCC could effectively retard the cover expansive cracking due to corrosion of reinforcing bars, and prolong the service life of concrete structures subjected to the environment being at risk of corrosion.
Study on the Application of Data Mining in the Reliability Evaluation of Structures
Authors: Hu Wei Bing , Hou Yan Fang
Published: May 2011

This paper studies several factors that affect the reliability of established structures .The theory of Data Mining is introduced into this paper as a new method to study the evaluation of established structures. New information is ultimately mined from “Data Sea” filed up in existed structures. According to the Chinese Structure Code and engineering experience, the factors affecting the reliability of structures are properly qualified as input parameters. This paper mainly researches with engineering structural examples on the theory of fuzzy cluster, which belong to the field of Data Mining. According to the analysis of the methods， it is found that the method put forward in this paper is practicable, reliable and effective.
Discussion of Mathematical Models of Probabilistic Constraints Calculation in Reliability-Based Design Optimization
Authors: Yi Ping
Published: May 2011

In a reliability-based design optimization (RBDO) problem, most of the computations are used for probabilistic constraints assessment, i.e., reliability analysis. Therefore, the effectiveness, especially the correctness of the reliability analysis is very important. If the probabilistic constraint is misjudged, the optimization iteration would have convergence problems or arrive at erratic solutions. The probabilistic constraint assessment can be carried out using either the conventional reliability index approach (RIA) or the performance measure approach (PMA). In this paper, the mathematical models to calculate the reliability index in RIA and to calculate the probabilistic performance measure (PPM) in PMA are discussed. In RIA, through estimating whether the mean-value point in safe domain or not, we should use a positive or negative reliability index respectively. In PMA, one should always minimize the performance measure to compute PPM whether the performance measure at the mean-value point is positive or negative, which puts right the wrong mathematical model in some literatures and makes it possible to produce effective and efficient approach for RBDO.
Experiment Design on Concrete under Load Attacked by Acid Rain
Authors: Niu Jian Gang , Zhang Zhen , Niu Di Tao
Published: May 2011

As the deterioration of environment, the effect of acid rain on concrete structures is even more serious. The durability problems caused by acid rain are increasingly concerned by the worldwide. In this paper, the method to simulating acid rain solution in laboratory is proposed and the cyclic soaking-drying to accelerate the acid rain attack is introduced on the basis of the survey and analysis on the components of acid rain around China. Considering that the majority of concrete structures are actually under loads, the load devices for durability test are analyzed, and the devices suitable for the multi-factor durability tests are adopted. The above works will be helpful to carry out the neutralization tests and establish the predicting model of neutralization depth for fly ash concrete.
Study on Indoor Comfort Zone of Residential Building in Beijing Region
Authors: Sun Chun Hua , Xia Guo Qiang , Yan Bing Hong , Zhang Xin
Published: May 2011

In order to research generalized apparent temperature model in Beijing region, the different age demographic composition proportion is considered and the existing apparent temperature model is modified on the basis of Steadman human heat balance equation. Then indoor comfort zone of residential building is obtained by generalized apparent temperature model reference to comfort zone of Beijing comfort index model. The generalized comfort dry-bulb temperature zone is acquired by critical value of generalized comfort zone. The critical value of generalized comfort dry-bulb temperature zone would be adopted to modify the outdoor start temperature of the central heating system and air-conditioning.
Intelligent Building and Green City
Authors: Lv Cai Zhong
Published: May 2011

Building automation system today employs an array of subsystems, communication protocols, data formats and software platforms. Some of these are proprietary, others are standards-based, but in neither case can true integration and interoperability be achieved. In addition to this, the traditional isolated subsystem within a building prevent renter and visitor from easily accessing the building resource and property manager from managing and maintaining the building. To address these issues, we describe a novel type of intelligent building system that merges IT technology with automation control technology. It allows devices from different manufactures to be integrated together seamlessly within one WEB-enable automation system; that enable property manager configuring, monitoring, and maintenance of heterogeneous subsystems with a unified application from a browser anywhere and anytime. It is seen that this approach provides the possibility to leverage current building automation technology into next high level.
Study on Strain Rate Effect in High-Rise Reinforced Concrete Shear Wall Structure
Authors: Zhang Hao , Li Hong Nan , Wang Zhe
Published: May 2011

The dynamic behavior affected by strain rate effect of the high-rise reinforced concrete shear wall structure subjected to seismic loading are analyzed by finite element software ABAQUS. The damaged plasticity model for concrete was used, and the strain rate effect of concrete and steel were considered. The nonlinear dynamic response results with strain rate effect are compared with the results without strain rate effect. The distribution of strain rate can not only influence the concrete and steel, but also have some effects on the dynamic response of the high-rise reinforced concrete shear wall structure. The strain rate effect is more prominent under the stronger seismic wave.
Precision of Earthwork Computation by Grid
Authors: Wei Hong Hu , Bao Yan
Published: May 2011

Based on theoretical models,the accuracy is analyzed to earthwork calculation in grid method under different terrain rolling rates, different grid widths.And the basic relationship between relative error of theoretical calculation and grid and terrain parameters is obtained, which can be used for evaluation of practical earthwork calculation.
Discussion and Practice in Monitoring of Open-Air Side Slope in Yinshan Lead Zinc Ore
Authors: Ma Da Xi , Xu Xiao Ming , Liu Xiao Hong
Published: May 2011

This paper introduced general methods of the GPS technology for open-air side slope deformation monitoring，and the entire process of the GPS deformation monitoring through the lead zinc ore open-air side slope in Yinshan，Dexing city, Jiangxi Province including technology design of monitoring network，field survey，data processing and deformation analysis．The results indicate that GPS static positioning technology reached the precision of mini-meter，has good advantages in the open-air side slope deformation monitoring and fully meet the requirements of high-precision deformation monitoring．
An Approach to Get building’s Facade Images at Short Distance
Authors: Wang Yue Qin , Wang Zhong Hua , Shuai Mei Xin
Published: May 2011

Digital images provide abundant information for the research of building deformation. However, such information is insufficient for the purpose of accurately measuring a building’s shape. This paper explores the method for restoring a building’s accurate shape from digital images. The relationship between oblique images and facade images can be analyzed to correct the distortion of a building’s facade images. The experimental results show that this practical method can meet the requirement of accurate measurement of a building’s deformation.
Research on Surface Deformation with Increasing Mine Depth
Authors: Chen Gang , Wang Qiong
Published: May 2011

After ore mined, the equilibrium state of original rock stress around mining area is damaged, causing surface deforming at large range. With the increasing resource needing and mining intensity, the mines all over the world are gradually in a stage of deep mining, so it is important to study the principle of surface deformation under the condition of deep mining. Finite element method is used to simulate mine process with increasing depth, and the relationship between mining depth and surface deformation is achieved. The result has important reference value to practical engineering.
Instant Built Tensegrity Structures with 3D Compression Members
Authors: Zhou Y.Y. , Li Jie , Frumar Jerome A. , Ren Gang
Published: May 2011

Tensegrity structures are of interest to architecture and engineering as a practical means to explore lightweight and rapidly deployable modular structures that have a high degree of geometric freedom and formal potency. The notion of tensegrity structures with 3D ‘compressed’ components is accreted by authors in 2009 [1]. This extended class of tensegrity overcomes some of the difficulties of typically ones by providing increased rigidity and more controlled structural behaviour. These two characteristics make 3D compression member tensegrity structures more suitable for practical use in building instant stand up structures. In this paper, the Authors introduce a method to create instant built structures with 3D Compression Members including the modules creation, digital form finding and assembling procedures. Exmple of a speculative design for a footbridge and a high rise building is demonstrated.
Study on Debonding Failure Behavior of RC Beams Combination Strengthened with Carbon Fiber Reinforced Polymer and Steel Plates
Authors: Xiong Xu Yu , Xu Hai Feng
Published: May 2011

In order to investigate the debonding failure mechanism,the distributions of interfacial shear stress between cracks and the influence of preload of on the ultimate load and interfacial shear stress,one reference beam and five beams strengthened with CFRP and steel plate at different level of perload were tested and analyzed.The experimental result indicated that the perload level has less influence on the ultimate capacity.Moreover,when debonding failure of sheet-end interface of concrete beams strengthened with CFRP and steel plate is avoided,the debonding failure of reinforced beams at perload level will occur in the position of midspan.At last,on the basis of cross-sectional equilibrium and compatiable conditions,an analytical model of interfacial bond shear stress is obtained, meanwhile the analytic model favorably matched with the experimental results.
Study on Bi-Stable Behaviors of Double-Layered Cylindrical Shell
Authors: Wu Yao Peng
Published: May 2011

Bi-stable structure can be stable in both its extended and coiled forms. As a novel deployable structure, it shows a broad application prospect in the field of aeronautics and civil engineering, etc. Considered two cylindrical shells having the same flattening configurations, they can be closely bound together by applying external forces. And the corresponding double-layered cylindrical shell model is proposed. Expressions for the bending and stretching strain energies of the cylindrical shells are presented. Calculations show that total strain energy has two local minimal values, which reveals that the double-layered cylindrical shell has its bi-stability. The corresponding rolled-up radii are thus determined.
Stress Field Analysis of Mode II Periodic Cracks-Tip
Authors: Li Chan , Zhang Xue Xia , Zhang Jian , Cui Xiao Chao
Published: May 2011

The cracks-tip field on ModeⅡperiodic cracks of infinite orthotropic fiber reinforcement composite plate subjected to the concentrated force was studied. With the introduction of the Westergaard stress function and application of complex function theory and undetermined coefficients method, mechanical problem is changed into partial differential boundary value problem. Owing to the distribution of periodic cracks, stress intensity factor(SIF) depends on the shape factor, which is greatly influenced by the crack spacing and the crack length. The results show that interaction happens between the periodic cracks, and that scale effect of the stress intensity factor in cracks-tip is obvious.
Relevant Cubic Grain Plank Plastic Strain Ratio (R) the Theory Research and Experiment
Authors: Yue Wen Xia , Wu Lang , Cheng Li Min
Published: May 2011

This paper shows that different materials have different quadratic functions, tensor function theory can make the function of history to represent the plastic strain, which can be a sheet metal pressing does uniaxial tensile test show that the plane of sheet metal, sheet metal specimen axis and the angle between the rolling direction changes, to the metal plastic strain ratio (R) along with the changes. To explain this phenomenon, the introduction of a quadratic yield function to describe the experimental results of some of the metal sheet. This paper shows that different materials have different quadratic functions, tensor function theory can make the function of history to represent the plastic strain, which can be a sheet metal pressing does not depend on the value of history.
Optimal Design of Spatial Grid Structure Using Group Search Optimization
Authors: Yuan Bing , Ren Feng Ming , Zhong Gen Quan , Zhou Jing
Published: May 2011

An economic and safety design proposal of the spatial grid structure is very difficult to find according to traditional design method.The group search optimization and its improved algorithm are applied in optimization design of a spatial grid structure in this paper. In this paper the finite element model of the spatial grid structure is firstly built through the platform of ANSYS. Then based on the parameterized programme language ADPL of ANSYS ,the group search optimization (GSO) and the quick group search optimization(QGSO ) are compiled ,the optimization analysis of the spatial grid structure are carried out. Finally, the optimization results and the optimization one from ANSYS are compared. It show that the optimization methods hereinbefore are feasible and the design proposals of them are better than the one of ANSYS.
Application of QR Method for Analysis of Spatial-Mega Frame Structure
Authors: Pan Wen Jun , Ye Xian Guo , Chang Lei
Published: May 2011

With the generalized displacement parameters of spline knots chosen as basic unknowns, the node displacement functions of spatial mega frames were built up, then element node displacements could be expressed by these parameters. New stiffness equation of spatial mega frame was deduced according to energy variational principle. The nodal displacement and nodal forces were worked out by the displacement parameters of spline knots. Process of block assembling for spline-discretization matrix was introduced briefly. One spatial mega frame was calculated by QR method and different finite element softwares. Comparation among the results and those of references proves that QR method is exactly an economical, effective and reliable method for computation of spatial mega frames. It provides a new approach for simplified calculation to spatial mega structures, so has good theoretical and practical value.
Research on Effect of Activation on Concrete with High Volum Ceramic Waste Mud
Authors: Han Yue Xin , Li Li Xia , Wang Ya Qin , Huang Fei
Published: May 2011

In this study an attempt has been made to find the suitability of the ceramic waste mud as a possible substitute for conventional concrete. Experiments were carried out to determine the flexural and compressive strengths of concrete and the modulus of elasticity of mortar with various activators. The result indicated that cement could be partly replaced by ceramic waste mud. The strength of concrete verious as the activator changed, so the key to increase the strength of concrete is to find the proper activor.
Influence of Mixing Equipment on Asphalt Mixture Segregation
Authors: Xie Li Yang , Zhao Li Jun , Yao Yun Shi , Zuo Wen Jun
Published: May 2011

In order to improve mixing quality of asphalt mixture, a method of theoretical analysis and test was used to analyze the effects of negative pressure of drying drum, geometric parameters of mixer and aggregate variation ratio in hot aggregate bins on the segregation of asphalt mixture. Reasonable measures of controlling segregation in the mixing process were given out. Research results indicate that stable negative pressure of drying drum reduce the temperature segregation of asphalt mixture by controlling temperature undulation of hot aggregate and reasonable arrangement of mixing blades cut down material segregation of asphalt mixture with adequate mixing. That isn’t all, delivery proportion of the aggregate in hot aggregate bins and mesh size of vibrating sieve, properly selected according to the gradation of cold aggregate, improve quality and efficiency of asphalt mixture with lower aggregate variation in hot aggregate bins.
Construction Technology of Large-Span Hybrid Structure of Suspendome with Stacked Arch in Chiping Gymnasium
Authors: Wang Xiao Bei , Liu Zhen Hua , Gong Ming , Weng Lian Fen
Published: May 2011

Large-span hybrid structure of suspendome with stacked arch is applied into steel roof of Chiping Gymnasium. The construction of this new type structure system is difficult according to structure characteristics such as its large-span stacked arch, high installation altitude, lattice shell installation, prestressed cable tension, and tight construction period. Temporary support frame, segment lifting and high altitude splicing construction method is adopted to install the stacked arch, and total support, high-altitude spread operation method is used to install lattice dome. A spatial structural analysis is conducted on the supporting system, and the finite element software is adopted to simulate and analyze the installation process of the steel structure roof system. At the same time, stress and deformation of the roof structure are monitored by precise instruments and equipments. As the result, construction safety and quality are guaranteed.
Design and Construction of the Support Structure of Deep Foundation Pit for a Cement Plant in SR Vietnam
Authors: Wang Ding Tang
Published: May 2011

Combined with a specific foreign-related project and based on the detailed report of the engineering geological investigation, this paper describes the application of the selected support structures of shotcrete-bolt and bored piles with high pressure rotary jet grouting waterproof curtain from aspects of scheme optimizing, design and construction, underground watertable lowering and result monitoring. Satisfactory achievements have been made in cost saving, shortening duration, facilitating construction and environmental protection etc. It demonstrates that two or multiple support systems can be used simultaneously in one foundation pit as support structure.
Experimental Research on Structural Damage Alarming of Benchmark Structure Based on Empirical Mode Decomposition
Authors: Cao Li Lin , Li Ai Qun , Deng Yang
Published: May 2011

A structural damage alarming method is proposed using empirical mode decomposition. The basic idea of this method is that with respect to the intact model and damaged models, the energy redistribution of the intrinsic mode functions decomposed from the structural response can represent the variation of the structural dynamic characteristics caused by the structural damage. By taking the Benchmark test model as the research object, the structural dynamic responses from the hammer-impact tests are collected then the damage alarming parameters and the damage alarming indices are evaluated. The experimental results reveal that the structural damage alarming indices based on empirical mode decomposition is able to effectively detect the structural initial damage with preferable damage alarming capacity.
The Exploration of Water-Saving in Building Water-Drainage
Authors: Cao Shuang Mei , Feng Gui Yun
Published: May 2011

Through the analysis of the present situation of water-saving in building water supply and drainage in our country to realize that some problems still exist in the water conservation consciousness, water saving technology, water-saving management etc, stating there is great space in water-saving, to ensure the water-saving society construction and save and protect the water resource, we should further improve water saving consciousness, changing the traditional water-using habits and improve water management way; Constantly innovating water-saving technology, researching and promoting water-saving facilities and equipment. dominated by the government, Comprehensive use of publicity and measure of administrative, law, management, economy, education and scientific means, unifying management, configuring scientifically, only this can solve the conflict of supplying and demanding to a certain extent and the lack of water in peak hour, it can ease the tension in water supply and protect the environment, bringing good environmental, social and economic benefits.
Aggregate Shape Effect on Mesoscale Modeling of Concrete under High Strain Rate Tension
Authors: Zhou Xiao Qing , Xia Yong , Huang Wen
Published: May 2011

Concrete might be subjected to impact or blast loading. To analyze the concrete behaviors under such loading cases, it is of interest to study the dynamic damage and failure behavior of concrete under high strain rate. In the present paper, a mesoscale model is developed to numerically analyze the dynamic damage process of concrete samples under high strain rate tension. In the mesoscale model, the concrete is regarded as a three-phase composite consisting of coarse aggregate, mortar matrix, and interfacial transition zone (ITZ) between the aggregate and the mortar matrix. Different coarse aggregate shapes, such as circular, oval, and polygon, are calculated and compared. It is found that the shapes of the coarse aggregates do affect the tensile strength and failure pattern.