bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural Damage Presence Detection from Time-Varying Modal Parameters in Earthquake
Authors: Gong Mao Sheng , Sun Jing , Xie Li Li
Published: May 2011

The objective of the paper is to present a method for structural damage presence detection from the time-varying modal parameters identified from the seismic response records in great earthquake. The time-domain system identification method RARX (Recursive Auto-Regression with exogenous variables) model is adopted to identify the time-varying parameters including modal frequencies and damping ratios from the seismic response data. Then the damage presence is detected from the change of parameters during earthquake. A 7-story reinforced concrete building, which had suffered moderate damage and recorded seismic response in Chi-Chi Earthquake, is used for the analysis. It is found that the damage presence can be determined from the decrease of the modal frequencies or the increase of damping ratios, and the time at which the building is damaged can also be detected from the time-varying modal frequencies. The results can be considered as the supplement materials for structural safety evaluation, structural damage investigation and related works.
Numerical Simulation Analysis on Explosion Stress Field of Different Charge Construction
Authors: Zong Qi , Yan Lu Ping , Wang Hai Bo
Published: May 2011

There are different blasting stress field which around the blast hole caused by different charge when explosives exploded in the rock. Simulation analysis on borehole wall pressure and explosion stress field of rock at different charging structure was done by ANSYS/LS-DYNA. The simulation results indicate: stress of coupling charge is the maximum, water-decouple charge is the latter and air-decouple charge is the minimum; and whether air-decouple or water-decouple charge, peak stress value of model decreased along with the increasing of decouple coefficient, but the air-decouple charge show more obvious. Therefore, water-decouple blasting has good energy utilization.
Experimental Study on Highway Tunnel Surrounding Rock Reinforced by Small Pipe Pre-Grouting
Authors: Wang Hai Bo , Lu Peng Ju , Zong Qi
Published: May 2011

Small pipe of staggered by length leading-drilling and grouting support technology was adopted for per-reinforcement of Lion-shaped Tunnel typeII rock, cement paste filled into loose rock mass rock fracture for adglutinate broken rock into a integrality, thus enhance the coherence and solidity of rock. Thesis introduced process flow of small pipe drilling grouting, grouting equipment, grouting parameters selection and practical applications. Through tunnel deformation monitoring and analysis, grouting reinforcement has achieved very good effect.
Comparison of Post-Buckling Behaviors of a S-S FGM Beam under Conservative and Non-Conservative Distributed Forces
Authors: Li Qing Lu , Li Shi Rong
Published: May 2011

Based on the large deformation theory and considering the axial extension of the beam, the governing equations of post-buckling of a simply supported elastic FGM beam subjected to conservative and non-conservative distributed forces were established. In the analysis, it was assumed that the material properties of the beam vary continuously as a power function of the thickness coordinate. By using shooting method, the nonlinear boundary-value problem was solved numerically and the equilibrium paths as well as the post- buckling configurations of the deformed beam were presented. A comparison between the results of conservative system and that of non-conservative systems were given. The results shows that the features of the equilibrium paths of the the functionally graded beam under non-conservative are evidently different from those to a conservative one.
The Increasing Laws of the Foundation Strength and Civil Engineering
Authors: Qin Zhi Hai , Li Tong Dong
Published: May 2011

In the civil engineering construction, with the building load of building construction or adding storeys, foundation pit dewatering, embankment filling , over time, the pore water stress that is borne by pore water in the foundation decreases gradually, the effective stress that is borne by particle increases gradually, the foundation bearing capacity increases gradually, we use different methods to derive the variation law in the theoretical solution, and carry on the comparison, then get the same conclusion. By using theory to solve the frequently encountered problems during civil engineering construction, including the problems of building construction or adding storeys, foundation pit dewatering, embankment filling, it provides theory basis for both economical and safe civil engineering construction .
Longitudinal Seismic Response Analysis of MSSS Bridge in Qinghai-Tibet Railway
Authors: Li Yong Bo , Zhang Hong Ru , Li Chun Feng
Published: May 2011

This paper presents the results of seismic behavior analysis of a multi-span simply supported (MSSS) bridge in Qinghai-Tibet Railway. The main goal is to examine the effects of frozen soil condition and wave passage on seismic behavior of MSSS Bridge. A 2D FE model was established by ANSYS software in order to evaluate the effects of modeling, in which bearings and pounding effects were also considered. Results indicate that frozen soil condition has an important effect on the seismic response in longitudinal direction; wave passage can influence the seismic response of MSSS Bridge within a certain range of seismic wave travelling velocity.
Application of Proper Orthogonal Decomposition Technique in Wind Engineering of Structures
Authors: Chen Ming Yang , Zhang Jian Sheng , Zhou Guan Gen
Published: May 2011

Dynamic wind pressures acting on structures are complicated functions of both time and space. The proper orthogonal decomposition technique (POD) is a method of detecting a new coordinate system which can most efficiently represent such random wind pressure fields to identify hidden deterministic structures. In this paper, the POD technique is applied to dynamic wind pressures on spatial structures in order to investigate the properties of these pressures and enable to understand the phenomena better. The results indicate that the POD technique can greatly reduce the amount of data that needs to be stored to re-examine the random wind pressure, which can be reconstructed by only a few dominant modes. It requires 5 modes with an accumulative proportion of 70~80% approximately. Moreover, the dominant modes can describe the spatial distributions of the fluctuating wind load effectively.
An Analysis of Rainfall-Induced Landslide in Colluvial and Eluvial Soils Overlying Xigeda Strata, Southwestern Sichuan, China
Authors: Zhu Bao Long , Wu Xi Yong
Published: May 2011

In late-July, 2005, a series of thunderstorms dropped 10 cm of rain in a 72-h period over southwestern Sichuan province. The storms also triggered more than 17 shallow landslides along the Lama Stream, about 2.5km from Jiuxiang Town, in Hanyuan County. Almost all of the landslides were translational, occurring along the contact between colluvial and eluvial soils and the underlying bedrock (claystones, mudstones, siltstones). 1# landslide was selected in the affected area for a detailed study of the shallow landslides. The record was made of the stratigraphy, slope geometry, landslide dimensions, hydrologic conditions, and contributing factors. Both colluvial soils and underlying bedrock were sampled for laboratory investigations, which included determination of natural water content, specific gravity, natural density, Atterberg limits, coefficient of consolidation, permeability, and shear-strength parameters. Data from laboratory tests were used to perform stability analyses by the infinite-slope analysis method, with respect to varying slope angles, strength parameters, and thicknesses of saturated colluvial and eluvial soils. The results of the study indicate that the shallow landslides of Xigeda strata occurred when the colluvial soils reached 90% to 100% saturation, depending upon the slope angles. It provides a basis for taking reasonable reinforcement measures for the landslides.
Shallow Discussion on Measures for Improving Indoor Air Quality
Authors: Tang Li , Tang Zhong Hua
Published: May 2011

By preliminarily study and evaluation of indoor air quality issues origin, causes, influence and purpose of the research, the paper puts forward five controlling factors including: the source control and eliminate indoor pollution, air conditioning equipment optimization design, ventilation efficiency, indoor air self-purification -- green plants elimination method, architecture design should follow the principle of design of ecological environment.
Low Carbon Community Planning Research - To Sun Xing Village Community for Example
Authors: Jiang Xiu Juan , Guo Zhan Jun
Published: May 2011

Under the background of global warming, the concept of "low carbon" comes into being. The author puts forward the concept of low carbon community from the view of urban planning, and suggests some steps for it: The planning is carried out from Intermediate perspective, include status, location, land layout, transportation system, supporting facilities, the green space system and so on, from microscopic stratification, include water environment, energy planning, low carbon garden design and so on.
Research on the Crack Stability of Dam Concrete Based on the Measured Monitoring Data
Authors: Guan Jun Feng , Hu Yu , Zhao Shun Bo , Qing Long Bang , Li Qing Bin , Zhang Li Hong , Luo Dan Ni
Published: May 2011

This paper proposes a theoretical expression for the ultimate relationship between the crack gauge monitoring data and steel stress gauge ones in dam concrete, based on the equation for crack width of reinforced concrete member, when the cracks expanded to the crack-control steel. In addition, a practical method is developed for analyzing and determining the crack stability of dam concrete, which predicts whether a crack elongated to the crack-control steel or not by comparing the observed values to the theoretical ultimate value. The provided method is proven to be proper to evaluate the crack stability of dam, which is simple and practical.
Preliminary Research on Behavior of CFST Columns after Exposure to Overall Stage of Fire
Authors: Wang Jing Xuan , Zhang Peng Peng , Wang Wen Da
Published: May 2011

A finite element analysis (FEA) model was proposed to predict the behavior of concrete-filled steel tubular (CFST) columns at overall stage of fire combined load based on ABAQUS. The whole stage includes initial loading, heating, cooling and post-fire phases. Accurate thermal and material model, element type, and solution method were chosen reasonably in the model considering the temperature and combined load. Due to lacking of test data about multi-phase of fires, the FEA model was verified with tests at different stages respectively. Some experimental specimens under different thermal and mechanical conditions were modeled using the FEA model, and the results obtained have good agreement with the experimental results. The mechanism of the CFST columns after exposure to overall stage of fire was also investigated based on the model.
A New Method to Select Seismic Records for Time-History Analysis to Hydro-Structure
Authors: Zheng Heng Xiang , Zhang Zong Min , Liu Jin Shuan , He Rong
Published: May 2011

In order to make sure the structures have well seismic performance, the designer adopt dynamic time-history analysis method .But there is a problem to calculate the dynamic response of the structures which is how to find a scientific and reasonable criterion to select seismic wave records. In order to solve this problem and find a scientific and proper criterion to select seismic wave records, this paper referred to the standards ruled by the new Chinese Seismic Design Code for hydraulic structures and used the numerical analysis and scientific computation, conducted a well meticulous analysis, then put forward one way to select seismic records for time-history analysis method of hydro-structure. Except for taking the site condition, the fortified intensity, the duration into consideration, the author also give more emphasis on the fitting degree between the response spectra of seismic records with the new code to provide better fitting degree.
Numerical Test of Crack Propagation Path in Asphalt Beam Using Coupled Extended Finite Element with Field Variable Method
Authors: Cao Peng , Feng De Cheng , Ma Hong Yan , Zuo Wen Xin
Published: May 2011

Based on extended finite element coupled with field variable method, fatigue damage numerical test of three point-bending beam with initial notch has been made to predict crack propagation path, numerical results showed : under the fatigue loading with 200Hz, and amplitude is 20KN, length of crack expanding was the biggest and crack grew as some angles with the initial crack during the first loading, crack propagated parallel to the initial angle during the other loading cycle. These results can fit the experiment very well. Using Fortran, A new user subroutine named USDFILD (User subroutine to redefine field variables at a material point) was also provided on the platform of ABAQUS, which can modal the change of physic material with time. This user subroutine can also import fatigue characterize of material into the model.
Experimental Research on Dielectric Constant Model for Asphalt Concrete Material
Authors: Zhang Bei , Zhong Yan Hui , Liu Hua Xue , Wang Fu Ming
Published: May 2011

Aiming at the problems of the applied technology of ground penetrating radar(GPR), the rationality and applicability of some common existed dielectric constant models to asphalt concrete material are verified and modified based on experiment, and then the new dielectric constant model models suitable for asphalt concrete material are established. The new models are applied to the real project, the results show that the new models can explain the characteristics of asphalt concrete material more accurately, and the calculated error of the compaction of pavement structures based on the modified models is significantly reduced compared to that based on the existed models.
Mechanical Analysis of the Recycled Concrete Brick Masonry Wall under In-Plane Load
Authors: Gu Song , Chen Guo Ping , Zhu Shui Wen
Published: May 2011

The purpose of this paper was to investigate the mechanical behavior and failure mode of recycled concrete brick masonry wall under cycling in-plane load. These models of masonry walls were constructed in the laboratory and experimented under in-plane cycling load. The masonry wall was made of recycled concrete bricks joined by mortar, with gypsum lining on both faces. A simulation based on the experiment was carried out using the finite element software ANSYS. In the proposed FE model, the recycling concrete bricks and joints were modeled separately, allowing for nonlinear deformation characteristics of the two materials. The results of the experiment and the finite element analysis were analyzed and compared. When the stress distributions were taken into consideration in the experiments and solutions of ANSYS, it was observed that the stress concentration occurred on two diagonals of the masonry wall. The destruction process and characteristics of the masonry wall were obtained by the experiments. The results of finite element method matched experimental results very well. The FE software ANSYS can be used in the analysis of recycling concrete brick masonry walls under in-plane cycling load and strength capacity.
Corroded Mechanism and Repair Technology of Concrete Buttress of Irrigation District
Authors: Xu Cun Dong , Wang Yan , Zhai Lu Xin , Hou Hui Min , Sun Yan Wei
Published: May 2011

Based on the mechanism research of pipe buttress corroded by the high salinity groundwater, this paper suggested that the corrosion problem can be solved by improving the anti-corrosion capability of the buildings in itself and reducing erosive medium. This paper put forward some repair technology and prevention method worthy popularization for corrosion of concrete buildings in irrigation district.
Experimental Study of Dynamic Properties for Serially Isolated System
Authors: Zhang Dong Bing , Jiang Xiang Lin , Liu Yan Hui
Published: May 2011

This paper presents a new-style isolation device for serially isolated system by the dynamic analysis to serially isolated system. This device has small horizontal stiffness and the difference of this device with rubber-lead bearing is that this device can resist biggish vertical tensile force. Then the experiment for small-scale model of this device based on sweep sine shaking table is processed. The results show serially isolated system with this device can prolong natural period of serial system and effectively decrease the response of superstructure and have good isolated performance and stability.
The Influence of Basin Excavation on the Sheet Pile Structure
Authors: Gui Jin Song , Meng Qing , Li Zhen Guo , Zhang Bo
Published: May 2011

In this paper, the basin excavation process is numerically simulated by using the geotechnical engineering software PLAXIS, and the bending moment, deformation and anchor bar tension of sheet piles under different excavation methods are obtained. The influence in different basin excavation methods on internal force and deformation of the sheet pile is studied by the non-linear finite element method. The results show that, if the construction process was piling before excavation, the maximum bending moment at mid-span, the maximum bending moment in buried section, the maximum horizontal displacement and anchor bar tension of the sheet piles would be bigger than the results without considering the influence of basin excavation. Therefore, the influence of basin excavation sequence should be seriously taken into account in the sheet pile design and construction.
A New Shape of Snaked-Lay Pipeline
Authors: Liu Yu Xiao , Ge Tao , Li Xin , Zhou Jing
Published: May 2011

Snaked-lay pipeline is an effective method for control lateral buckling of pipeline, which is used widely. For design of snaked-lay pipeline the key is how to control lateral buckling of pipeline, namely, the lateral buckling is triggered at the designed location, the moment and strain of post buckling are acceptable. A new shape of snaked-lay pipeline is presented. Based on ANSYS, nonlinear finite element of pipeline is built. Comparisons show that the critical buckling load, moment and strain of post-buckling are all reduced for the new shape of snaked-lay pipeline.
Thoughts and Countermeasures on Adjustment of the Regulatory Detailed Planning
Authors: Wang Zheng , Xiong Juan
Published: May 2011

Based on the current situation that the regulatory detailed planning is being adjusted frequently in most cities in China, the contents and problems of the regulatory detailed planning are summarized. Later on, the causes and disadvantages of the regulatory detailed planning alteration are analyzed as well, in terms of urban planning formation, the interests of developers, urban planning management, and etc. In the end, the countermeasures and advice which can promote the effective implementation of urban planning are put forward.
Calculation of Ultimate Bearing Capacity of Prestressed Steel Reinforced Concrete Structure under Fire
Authors: Wang Yu Zhuo , Fu Chuang Guo
Published: May 2011

Prestressed steel reinforced concrete structure, compared with other concrete structure has its unique advantages. So it is mainly used in large span and conversion layers. With the popularization of this structure,more attention should be payed on fire resistance performance. On the basis of reasonable assume,two steps model is used as concrete high strength calculation model. Simplified intensity decreased curve is used as rebar,steel and prestressed. Two ultimate bearing capacity formulas of prestressed steel reinforced concrete beam are established. One is for the beam whose tensile area is under fire, the other is for the beam whose compression area is under fire. Prestressed steel reinforced concrete structure has both prestressed concrete structure’s advantages and steel reinforced concrete structure ’s advantage. Steel reinforced concrete is used to improve the bearing capacity of the structure. Prestressed steel is used to improve the ultimate state of structure’s performance during normal use. Thereby structure’s performance is better to play. There are many similarities between prestressed steel reinforced concrete structure and steel reinforced concrete structure about fire resistance performance. Because of prestressed steel reinforced concrete structure’s own characteristics, there are still many problems about fire resistance. This paper mainly presented bending terminal bearing capacity of prestressed steel reinforced concrete beam under fire. Established simplified formulae for calculation, it is meet the engineering accuracy requirement.
Test Study on Water Problems after Barrier Construction in the Jinjiang Estuary
Authors: Zhang Xing Nong , Chen Chang Ying , Zhang Si He , Ying Qiang
Published: May 2011

For improving water scenery of Quanzhou city to form a good-looking artificial lake, a barrier is planned to be built in the Jinjiang estuary to store up water from runoff and tide. Some water problems dealing with the barrier construction in the lower reach of the Jingjiang River, such as city flood control and draining waterlogging, water quality, ship passing, and so on, also are concerned by many aspects of whole society. Detail research on these problems for providing a basis of design and operation of the barrier was performed in Nanjing Hydraulic Research Institute according to a physical model test. The result shows that there is a small impact to flood running, and disadvantageous impact to water quality can be reduced to minimal extent by reasonable operation manner of the barrier.
Periodical Urban Morphology Evolution Research of Representative City in Songhua River Basin
Authors: Cai Xin Dong , Guo Hai Bo , Huang Meng
Published: May 2011

The paper takes the examples of three representative city including Jilin, Harbin and Jiamusi, analyzes the phased evolution characteristics of urban morphology on the basis of internal relation between the cities and the water environment of Songhua River.
Analysis and Design Recommendations for the Collapse of a Concrete Silo
Authors: Yuan Guang Lin , Tian Lu Dan
Published: May 2011

Accidents of the cement manufacturers’ reinforced concrete silo structures frequently occurred currently in China, because of quality problems, causing enormous losses. The collapse status of a cement raw meal silo is investigated. Combined with the test results of the location and spacing of silo wall’s reinforcing bars, concrete strength, cracks and defects, the reasons for collapse of silo wall are analyzed and design recommendations for concrete silo structures are made. This can give reference to reinforced concrete silo structure design and construction in the future.
Research on Time Series Analysis Based Deformation Prediction Model
Authors: Zhang Hao , Shi Xi , Lai Li Fang
Published: May 2011

This paper introduces a method to apply time series analysis in dam deformation monitoring and prediction. We provide a simplified AR prediction model, which is relatively optimized in fitting constructive dynamic deformation features, analyzing deformation data and predicting deformation trend. We use this AR model in a certain dam’s deformation data processing, and prove it is an effective dynamic deformation prediction model.
Analysis on Dynamic Response and its Optimized Design of Penstock and Expansion Joint Structure in Hydropower Station
Authors: Gu Hua , Yan Gen Hua
Published: May 2011

During electricity generation in the power station, the dynamic pulsating loads bring about vibration on penstock and expansion joint structure and lead to fatigue damage. This essay is mainly about doing research on flow-induced vibration response of power station expansion joint structure, putting the flow pulsating pressure load of expansion joint tested into numerical model to calculate, and making evaluations about its engineering safety. With regard to the problems existing in this engineering project, we bring forward the corresponding design proposal of optimization. The results of calculation indicate that the optimization program has a significant effect on controlling the decreasing amplitude of the max displacement and stress, which makes sure of the safety of generating system.
A New Algorithm for Normal Water Depth of the Ordinary Arched Tunnel
Authors: Wen Hui , Li Feng Ling
Published: May 2011

Arched section consisted of a rectangle and a semicircle part. It is commonly applied in the field of hydroelectric engineering. The normal water depth computation equation for an arched tunnel is a transcendental equation and no analytic solution. In this paper, based on the mathematics transformation for the basis equation and the relationship analysis between the dimensionless normal water depth and the relative parameters, a new linear solution formula are established for the calculation of normal water depth for arched section tunnel according to the fitting principle. This method overcomes the shortage of other iterative trial calculating methods, such as complex calculation step, depend on the special chart and curve, and existed serious error. The new formula is simply and the maximum error is less than 0.6156% under the general engineering design range (ratio of normal water depth and arch radius is between 1 to 1.5416). it can be used on the engineering designing practice and the edit of the handbook of hydraulic structure design.
Decoration Project Cost Control and Management Based on Process Approach
Authors: Xu Qi Wen , Gong Cheng Long
Published: May 2011

With the rapid development of the real estate industry of china, the architectural decoration companies have been getting a good chance to prosper and develop. But it also faces to many problems, such as the increasing costs, the decreasing profit rate and so on. This paper presents an issue of using process approach and project lifecycle to manage decoration project, so that the decoration project management validity, constructing quality and construction cost control efficiency could be ensured well.
A Study of Guide Rules and Genre Studies of Urban Underground Space Development from the Perspective of Compact City
Authors: Zhao Jing Wei
Published: May 2011

Only by making intensive use of land to achieve highly compact, can a city achieve functional concentration and optimization to promote the urban sustainable development. To exploit urban underground space, the irreversibility of development should be considered and the guide rules and genre analysis of urban underground space development should be made with the emphasis on exploiting earth-covered construction, underground public buildings and underground complex.
Numerical and Experimental Investigation on Smoke-Buffer Effect of Different Smoke-Control Combination in Corridor
Authors: Li Jing Xian , He Jia Peng
Published: May 2011

In this paper, full-scale experiments had been designed and implemented in wind tunnel to simulate the corridor fire. A combination model with smoke buffer and other smoke-control modes was established on the base of experiment, and Fire Dynamic Simulation (FDS) was applied to simulate fire in the same conditions. The results reflected that the model is reasonable and viable by compared the simulation results and the experiment dates and the error of the average temperature is about 4.08%. Experimental studies also show that in those modes one smoke outlet is needed every 30m and it is better to set near the ignition source. Its exhaust efficiency is 72.1%, better than others; additionally it needs to put up smoke screen to strengthen the smoke exhaust effect. Thus the best combination with smoke-control is perfect in corridor.
Test and Research on Frost Resistance Durability of Elastocoast® PUR-Stone
Authors: Liu Li Jia , Zhang Bin , Sun Jing Lu
Published: May 2011

Based on the research on the frost resistance durability of Elastocoast® PUR-stone, this thesis provides a comparison and analysis of the flexural strength, compression strength and quality loss of Elastocoast® PUR-stone after 300 times freeze-thaw cycling, concluding that reduction in both flexural strength and compression strength occurs after 300 times freeze-thaw cycling of Elastocoast® PUR-stone while no distinctive change in quality loss is observed, which testifies to a certain degree of freeze-thaw resistance of the material.
Contact Analysis on the Longitudinal Joint of Gravity Dam
Authors: Cui Jian Hua , Xiao Han Jiang , Shan Liang
Published: May 2011

In order to understand the contact condition of longitudinal joint of gravity dam and its influence on dam body stress, taking a concrete gravity dam section as the research object, the numerical simulations with 3D nonlinear FEM is carried out through the simulating of the construction period, the grouting process and the operation period. It shows that the opening of the longitudinal joint varies with many kinds of factors, such as the year temperature, water cooling, water load on the upstream surface, the construction process and so on. Under the present condition, secondary grouting to the longitudinal joint may not be carried temporarily. The computation results are basically in agreement with the prototype monitoring data.
The Practice and Thinking on the Coordination between Urban Plan and Land Use Plan - Take Yicheng City as an Example
Authors: He Yu
Published: May 2011

The conflict between urban plan and land use plan is an intricate problem. This paper will take Yicheng City as an example to analyze the cause of conflict between urban plan and land use plan. Then quantitatively study on the coordination between urban plan and land use plan based on GIS technology and provide a practical working route and technology method for the coordination of these two plans. Because of the promotion of working route and technology method, it achieves good effect on these two plan’s coordination process.
Finite Element Analysis of Air Cooler Using Equivalent Static Method and Response Spectrum Method Respectively
Authors: Hu Shao Qing , Sun Bai Tao
Published: May 2011

Based on the characteristic of cooler frame, the finite element model of air cooler frame is established using ANSYS software. Equivalent static load method and response spectrum method were used for the seismic performance analysis of cooler frame. The equivalent static load is applied at the center of gravity of various masses using MPC184 rigid beam for transferring the load. The deformation and stress of cooler using equivalent static load method are larger than that of cooler using spectrum response method. For this reason, it can be said that the equivalent static load method is more conservative. At last the deformations and stresses of cooler frame using two methods are checked by ASME AG-1 specification. The results showed that the deformation and stress of cooler frame meet the requirements.
Reserch of Horizontal Dynamic Stress Distribution on Dynamic Consolidation of Discarded Iron Slag
Authors: Song Xiu Guang , Dou Zhi Gang , Yao Kai , Yang Yang
Published: May 2011

Dynamic consolidation has been widely used in many engineering fields. But in the use of discarded iron slag filled embankment, because the discarded iron slag is naturally piled up, multi-size particle mixture and backfilling height is relatively high, the effect of simple dynamic compaction is not obvious. This paper, combined with engineering examples, through the dynamic consolidation test, describes the experimental program, arrangement and spacing of tamping point, and matters need to be taken care in construction. It also explains the horizontal effects in consolidation by detection data analysis of waste iron slag roadbed. In this paper, we have established finite element numerical simulation analysis of dynamic consolidation by using FLAC3D. It is available in roadbed practical application and can be reference in similar projects of dynamic consolidation.
Research on the Thermal Property of Lightweight-Aggregate-Concrete Hollow-Block Wall
Authors: Li Dan , Tao Jun Lin , Yu Jiang
Published: May 2011

The Theoretical calculation and the finite element method (FEM) are used for studying the thermal property of hollow-block and hollow-masonry. The method of appendix in the standard for Thermal Design of Civil Buildings is adopted to calculate the thermal resistance and the average thermal conductivity of hollow-block and hollow-masonry. ANSYS is used for simulating temperature distribution and heat flux law under connective loads. The conduction and convection phenomena are taking into account in this study for four different values of the mortar conductivity and four different values for the bricks. The thermal resistance and the average thermal conductivity of hollow-block and hollow-masonry is the key factor for reference.
The Effect of Anthropogenic Heat on Local Heat Island Intensity and the Performance of Air Conditioning Systems
Authors: Liu Jing , Ma Fei , Li Ying
Published: May 2011

Anthropogenic heat released from air conditioning systems is one of the most important factors contributing to the heat island in summer. A model to predicted heat island intensity is built. Using this model, a typical office building cluster is simulated, and the effect of heat released by air condition on outdoor thermal environment and heat island intensity is discussed. Furthermore, the reaction of heat island intensity rising on the performance of air conditioning systems is also investigated.
Computational Analysis of Performance of Smoke Exhaust System in Atrium Buildings with Nonuniform Spaces
Authors: Li Jun Mei , Li Yan Feng , Sui Jing , Liu Shan Shan , Wang Xin
Published: May 2011

Performance of the smoke exhaust system in two atria with nonuniform spaces will be analyzed by fire models in this paper. A two-layer zone model and a Computational Fluid Dynamics field model FDS developed by the Building and Fire Research Laboratory, National Institute of Standards and Technology, USA are used. Numerical results are compared with the experimental data by hot smoke test in these two atria. Both fire models can give good predictions and so are suitable for evaluating the performance of the smoke exhaust system.
Summarization of Pedestrian Flow Characteristic
Authors: Li Jian , Zhao Dong Fu , Liu Dong Dong , Zhuang Peng
Published: May 2011

Review both domestic and overseas pedestrian flow characteristic research results. Enumerate our country’s research achievements recent years. Introduce that the domestic scholars draw the pedestrian speed characteristic and pedestrian flow model according to different time, place, environment and other cases. Examples show that the pedestrian speed characteristic and pedestrian flow model has certain differences. For example, most domestic scholars describe speed - density relational expression with dynamics model, logarithmic model and linear model. This paper proposes that establishes reliability index for different pedestrian flow model, studies how different facilities affect the pedestrian flow characteristics, and establishes data reference standard for pedestrian flow characteristic.
Energy Absorption of Spruce Wood under Three Kinds of Quasi-Static Compression Conditions
Authors: Zhong Wei Zhou , Huang Xi Cheng , Hao Zhi Ming , Xie Ruo Ze , Chen Gang
Published: May 2011

The curves of stress versus strain along spruce wood axial, radial and tangential directions are gained by static compression experiments. Moisture content and density of the spruce wood are 12.72% and 413 kg/m3respectively. The results indicate that spruce compression process includes elastic, yield and compaction phases. Failure modes of spruce subjected to axial compression are fiber buckling and wrinkle. And failure modes under radial or tangential compression are wood fiber slippage and delamination. Axial compression yield strength is about nine times as that of radial and tangential compression. Radial and tangential compression yield strengths are almost equal. Energy absorption efficiency and ideality energy absorption efficiency of spruce along different loading directions are analyzed. And theory analytic solution to single wood cell buckling under axial compression is done. The obtained expression shows that the mean limit loading is relative to yield stress, cell structure dimension and wrinkle length for complete wrinkle cases.
Experimental Study on Pavement Performance for Sandy Soil Stabilized by Soil Stabilizer
Authors: Li Rui Duo , Yue Jin Chao , Yue Xu Dong
Published: May 2011

In order to protect natural environment and save construction cost, both the physical and mechanical properties and the strength change laws of stabilized sandy soil mixture were studied in this paper based on the characteristic of sandy soil stabilized by Lufeng-1 soil stabilizer. The results show that the pavement performance indexes of the sandy soil stabilized by soil stabilizer completely meet the design requirements of every pavement structure layer below base in certain proportion and the optimum proportions for pavement roadbed, sub-base and base materials also are recommended, which provide technological foundation for the utilization of sandy soil.
The Research of Pollutant Multiple Exergy Intensity Distribution in a Kitchen under Different Control Schemes
Authors: Jia Xin , Ao Yong An , Wang Li , Gu Chao
Published: May 2011

The aim of this research is to present a relatively ideal pollutant control scheme, through the comparative analysis of pollutant distributions with multiple exergy intensity in a household kitchen under four different control schemes. In this paper, in order to simulate kitchen pollutant diffusion and distribution, the neural network model is established and simulation software is developed on the platform of VC++ based on measured data.
A Novel Window Type Air-Conditioner with Energy Recovering
Authors: Luo Qing Hai , Zhang Peng Fei , Yang Xiu Fei , Zou Jun
Published: May 2011

A novel window type air-conditioner with energy recovering was experimented. The experimental prototype can make fresh air exchange heat with exhaust air in an additional heat exchanger, which consist no additional moving parts. The EER (energy efficiency ratio) of the experimental air-conditioner (EAC) is increased by 17.4~37.3% than that of the original ordinary window type air-conditioner (OAC). On the other hand, the fresh air proportion of the EAC is increased by 20% or so than that of the OAC, so indoor air quality can be greatly improved via the EAC; however the indoor noise of the EAC is increased by 3.2 dB or so. The novel experimental prototype is of great significance for energy efficiency.
Research on Elastocoast Revetments Frost Heave Adaptability Model Test
Authors: Zhong Hua , Zhang Bin , Wang En Liang
Published: May 2011

Elastocoast revetments frost heave adaptability model test was carried out. Conclusions: (1) Elastocoast revetments can increase heat resistance and decrease the energy transfer. So the frozen depth and amount of frost heaving could be reduced. (2) This structure has deformation characteristics with temperature, and has a deformation at the test beginning. (3) The freezing rate under revetments is slow and the water supply is sufficient, because of which the amount of frost heaving will occur at one third of side slopes of canal, and the bottom of canal take the second place. (4) Consolidation settlement occurred after freeze-thaw cycling. And the revetments have a trend of becoming gentle slope. It indicates that Elastocoast revetments can commendably adapt to frost heave deformation. (5) The freeze-thaw durability is influenced by water content and the dosage of Elastocoast. The capability to resisting freeze-thaw denudation is better with the water content reduce and the material dosage increase.
Study on the Action Mechanism of Bitumen Emulsion and Aggregate
Authors: Liu Hong Ying , Jia Yi Qin
Published: May 2011

The paper describes the action mechanism of bitumen emulsion and aggregate, the charge test of aggregate and reaction heat test between aggregate and bitumen emulsion are used to analyze adsorption mechanism. The results show that at moisture condition alkaline aggregate generally carry positive electric charges, while acidic aggregate negative charges. Interaction between aggregate and bitumen emulsion can be affected by affinity of the materials, extent of chemical reaction and electrical property on their surface, which can determine the mechanics properties of the mixtures. The adhesive coefficient can be used to evaluate adhesive property between aggregate and bitumen emulsion, Kad is the larger, the adsorption strength between aggregate and bitumen emulsion is the larger.
Effect of Different Initial Moisture Contents on the Characteristics of Coupled Heat and Moisture Transfer of a Reinforced Concrete-EPS Thermal Insulation Composite Wall in Harbin
Authors: Xu Yu Gong , Lu Mei , Jia Zi Le
Published: May 2011

This paper investigated the effect of different initial moisture contents on the characteristics of coupled heat and moisture transfer of a reinforced concrete-EPS thermal insulation composite wall in Harbin. The change of the moisture content with time and the change of the heat transfer coefficient with time of the reinforced concrete-EPS thermal insulation composite wall at different initial moisture contents in Harbin were numerically simulated. The relative humidity and the quantity of condensed water in the air layer of the reinforced concrete-EPS thermal insulation composite wall were also calculated. The paper provides a scientific proof for the influence of the process of construction of a reinforced concrete-EPS thermal insulation composite wall on the energy-saving of buildings.
The Multi-Resolution Watershed Model Based on DEM
Authors: Li Xiao Gen , Huang Zhi Quan , Jiang Tong , Wang An Ming
Published: May 2011

The multi-resolution flooding routing model advanced firstly is composed of the extensive flooding routing model and the fine flooding routing model. In the article to put up research and discuss detailedly the 3D visualization of the mul-resolution flooding routing model which is as the non-engineering measure about the water conservancy management. In the article to analysis the constructing method of the mul-resolution flooding routing model mainly ,which is the theory and method about the extensive flooding routing model and the fine flooding routing model constructed and to work out material the extensive flooding routing model and the fine flooding routing model. Finally to applying the statistic analysis method to get the below conclusion: ①Applying the visualization system about the multi-resolution flooding routing model is to act the non-engineering measure about the water conservancy management and it provides a new thought and trusty scientific decision-making for the water conservancy management department; ② The results of the storage capacity and the submergence area worked out by the the fine flooding routing model are more precision than the result of the general method. The above conclusion proves the feasibility and science about the construction of the multi-resolution flooding routing model adequately.
Optimal Layout of Pipe Network of District Cooling System in Shanghai EXPO Park
Authors: Feng Xiao Ping , Wu Hang Ming , Long Wei Ding
Published: May 2011

The layout of district cooling pipeline network is a typical combinational optimization problem. Taking the minimum annual total cost of pipeline network as the optimization target, this article applied the single parent genetic algorithm in optimum arrangement of aqueous cooling system pipe network of the First Energy Station in Shanghai Expo Park, which has given a scheme of arrangement with minimum tentative investment and operation cost to provide basis for scheme assessment and decision-making. The study shows that the application can provide not only many optimal arrangements for pipe network which has the same refrigeration station to make basis for scheme assessment and decision-making, but also the basis for choosing the best position of refrigeration station.
Analysis on the Expansion of Surface Crack in Asphalt Pavement
Authors: Lu Pei Juan , Yang Jie , Huang Cong Bin
Published: May 2011

The relationship between surface crack tip stress intensity factor and calculated parameters of pavement structure is discussed and finite element models based on the fracture mechanics theory is created. From the study in this paper, the following conclusions can be drawn: As the load increases, stress intensity factor will decrease, and it may promote spread of the crack. Surface layer modulus has a great influence on stress intensity factor. In the condition of the same crack depth, stress intensity factor increases while surface layer modulus increases, stress intensity factor decreases gradually while the thickness of the surface layer increases. As base layer modulus increasing, stress intensity factor of surface layer decreases. With the increase of the modulus of subbase layer, stress intensity factor of surface layer decreases gradually. The earthen foundation module has a little big influence. With the increase of the earthen foundation module, stress intensity factor will decrease, so it can delay the appearance of the crack.
Influence of Boundary Conditions on Modeling Seawater Intrusion into Coastal Aquifer
Authors: Liu Yi , Mao Xiao Min
Published: May 2011

Numerical simulation is an essential tool for investigation of seawater intrusion in coastal aquifer. For most groundwater modeling software, boundary condition along the beach is required. But it was normally assumed due to the uncertainty in the seawater – freshwater interface. Using FEFLOW, a groundwater simulation software based on finite element method, we investigated the intrusion scope and the exiting point of groundwater outflow under various boundary conditions. Seven cases were designed, among which three cases with boundary conditions of a freshwater layer over seawater, three cases with a triangle freshwater zone between seawater and the beach, and the last one without freshwater at the seawater boundary. Results showed that the last case has the longest intrusion scope. The scope of seawater intrusion is determined by both the horizontal water head gradient along the bottom of the aquifer and the vertical water head gradient along the beach. Both higher horizontal gradient and lower vertical gradient result in larger intrusion scope. In some circumstances, the vertical gradient has greater impact on seawater intrusion than the horizontal gradient, and act as the main power inhibiting seawater intrusion.
Inspection and Analysis for IAQ at the Waiting Room in Lingui Bus Station
Authors: Zhou Zhi Ping , Wang Rong , Huang Chao
Published: May 2011

Indoor air quality has an important impact on human health.In order to find out indoor air quality (IAQ) condition at the waiting room in Guilin Lingui bus station, in the survey, the waiting room IAQ had been investigated with the carry-home fast inspect instrument from Dec 20th to Dec 30th in Lingui Bus Station. The levels of CO2, formaldehyde(HCHO), particles with diameters of 10 um or less(PM10) and total volatile organic compound(TVOC) had been inspected mostly. Data were analyzed by the SPSS 11.0 and evaluated with synthetic index method of air quality. Results showed that CO2 concentration was biggest to 878 ppm(standard limit of 1000ppm), PM10 concentration was biggest to 0.14mg/m3(standard value of 0.15 mg/m3), HCHO concentration was biggest to 0.08 mg/m3(standard value of 0.10 mg/m3). The concentration of other pollutants were lower comparatively. The winter air quality of the waiting room in Lingui bus station belongs to the no pollution. It showed that the levels of indoor pollutant were higher than outdoors', too.