bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Splitting Tensile Strength of Shotcret Layer of High Temperature Tunnel
Authors: Zhang Yan , Li Ning , Zhang Hao Bo
Published: November 2012

The high-temperature tunnel at Buren mouth - kongur Hydropower in West Kunlun Mountains of Xinjiang, China exist significant temperature differences phenomenon, which affects the stability of the shotcrete layer in tunnel. Combining with on-site engineering practice, the insulation heating device is designed. The laboratory splitting tensile strength test is carried out on polyester concrete, polypropylene concrete, polyacrylonitrile concrete and ordinary concrete with thermal heating device at 25°C-90°C. The splitting tensile strength changes of concretes affected by temperature difference are analyzed. The results supply a directly guidance to the design of the concrete sprayed layer structure of high-temperature tunnel.
Research on Collision of Metro Comprehensive Pipeline
Authors: Zhao Qin , Bai Guo Liang , Hei Xin Hong , Zhang Peng Fei
Published: November 2012

As an important urban rail transit, the metro has become one of the standards to measure whether the city belongs to modern internationalized destinations or not. Though the space of subway station is relatively small, the metro comprehensive pipeline is an important part of the subway station and includes a huge variety and quantity. During the design process of metro comprehensive pipelines, pipeline collision happens frequently. On Three-Dimensional design platform based on BIM technology, pipeline design has already been mature. This paper puts forward adjustment algorithms about metro comprehensive pipeline collision and they are both flexible and easy to realize and adapt to any Three-Dimensional platform based on BIM technology
Numerical Simulation on the Influence of the Groundwater Flow Field during Tunnelling
Authors: Kang Xiao Bing , Hu Xie Wen , Xie Huai Qian
Published: November 2012

With the vigorous development of China's economic construction, especially since the western development, needs of traffic tunnel construction are increasing, a large number of tunnels will be built in the mountainous with deeply buried and high water pressure, it is an urgent problem about research on the groundwater environment and the ecological environment in the tunnel site area causes of tunnel construction. The Songpan County Mounigou tunnel located in the high altitude alpine region, regional and environmental geological conditions are complicated, the strata in the tunnel site area is aquifer, and developed faults fractures and fissures, tunnelling will lead to groundwater dewatering and cause the deterioration of the groundwater environment, Then great collapse, burst mud and water gushing will occur during the tunnel construction due to the enrichment of groundwater in tunnel site. Take a research on numerical simulation of groundwater flow in the tunnel site area, the tunnel excavation will form a larger catchment corridor, the impact is bound to the tunnel site hydrogeological conditions in the sphere of influence may appear to lower the groundwater level, seisensui drawdown or part of the dry, provide the basis for tunnel construction.
Research on Stability in Metro Tunnel Constructing with Shallow Buried Covered Excavation in Loose Sand Layers
Authors: Li Shen Gang , Zhao Wen , Cai Xiao Li , Ma Yin Fu , Zhang Lu
Published: November 2012

For subway tunneling in urban underground, high safty of construction is needed.However, the safty and rationality of excavating plan are forecasted difficultly because of consealment. Based on the Zhang-Shen tunnel construction of Shenyang subway, bench method, single side-wall heading excavation method and CD excavation method are numerical simulated; according to the numerical calculation results and the constructing process, bench method is adopted; the ground settlement caused by excavation monitored during excavating is in the allowed range and the tunnel is safe during excavating.
Construction Schedules Simulation and Prediction of Water Conveyance Tunnel Based on Karst Geological Condition
Authors: Bi Lei , Luo Jia Qian , Tong Da Wei
Published: November 2012

The construction process of water conveyance tunnel is complex and stochastic under the karst geological condition. Aiming at analyzing the construction process under this special condition, a simulation modeling method of water conveyance tunnel construction is presented. Through demonstrating the simulation analysis and predicting the schedules in a real case study of a water conveyance tunnel, this method is proved advanced and intuitive for formulating and analyzing the construction schedules under the karst geological condition.
Safety Analysis of the Vertical Shaft and Corresponding Safety Measures
Authors: Zhu Huan Le , Liu Xun Hua , Yao Xi Ping
Published: November 2012

Based on the engineering that shield machine’s passing through a vertical shaft in urban rail transit construction, two methods are proposed according to the engineering geology and construction organization and finite element model is established to simulate the real situation. After the technical analysis and safety analysis of the two methods, the recommended method is given, also given are the corresponding safety measures and construction procedure. The success of this engineering proves that this analysis is reasonable and the safety measures are worth of referring to.
Numerical Analysis on Top Coal Caving of 2# Coal Seam in First Mine of Chagannaoer
Authors: Li Qing Hai , Yang Ren Shu , Shi Wei Ping
Published: November 2012

In first mine of Chagannaoer, 2# coal seam, the mainly mined out layer, was 22.00m thickness in average. In order to meet the requirements of production ability, the mine was planned to apply mining technology of fully mechanized caving. Good or bad of top coal’s caving was an important prerequisite which decided the mining technology of top coal caving could be chosen or not. Due to lack of producing mines in this region and no experience to refer, we simulated the mining process of 2# coal seam using numerical software of FLAC3D, and gained evolution laws of stress and displacement of top coal and overlying strata and expansion laws of plastic zone. Through analysis, we got that the top coal damaged seriously and the top coal could be caved smoothly. Relying on the geological conditions of site, we verified the simulated results with method of fuzzy comprehensive evaluation. Combined with the research results, we decided that 2# coal seam’s caving was better and was convenient for top coal caving, so it was suitable for caving mining in 2# coal seam in first mine of Chagannaoer.
Geological Characteristics and Waterflooding Strategy for Yuanshi Low Permeability Sandstone Reservoir
Authors: Zhu Wei , Cao Zi Jian
Published: November 2012

Core test data from 10 wells indicate that the sandstone reservoir in Yuanshi oilfield is characterized by low permeability, thin pore throat, high clay mineral content, and strong sensitivity, which are likely to cause reservoir damage and affect development result. Based on the characteristics of water-sensitive, velocity-sensitive low permeability reservoir as well as non-Darcy flow behavior, the development strategy of high pressure water injection and cyclic water injection has been formulated with the assistance of engineering measures such as fracturing and reducing well spacing.
Coefficients of Settlement and Lateral Displacement in Pile Group during Tunneling
Authors: Wang Li , Zheng Gang
Published: November 2012

Finite element methods are adopted herein to study the group effect and sheltering effect in pile group during shield driven when the couple effect of vertical loads and soil displacement is considered. Results from the FEM show fine agreement with those from the Tianjin No.1 subway line project and the centrifuge tests carried out by Loganathan. Based on the finite element models, the effects of tunneling on pile groups are studied. The coefficients of settlement and lateral displacement are defined to assess the group effect and sheltering effect in pile groups with elevated cap.
Analysis of Equivalent Static Method for Subway Station
Authors: Chen Liang , Yang De Jian
Published: November 2012

Structural integrity of Subway station is a very important indicator when the earthquake happens as it is a densely populated venue. Time-history analysis of Tianjin metro line 3 based on the theory of coupling seismic load was done with the finite-element software ANSYS. Consequently, numerical expression of the equivalent load was fixed and the procedure of seismic check of subway station structure gets further simplified and necessary theoretical basis.
Experiment Data Analysis of Comparative Test Research on Expressway Asphalt and Asphalt Mixture
Authors: Hu Ying De , Xiong Mao Dong , Yu Tian Tang
Published: November 2012

Nine test lab comparative test indexes of asphalt and asphalt mixtures are analyzed by consistent statistic analysis method of ASTM E691 and Robust statistical analysis method, analysis results indicate that two methods are basically in consistent with each other, but dubious analysis index is added in Robust statistical method, and reliability is possibly enhanced on data analysis. Combined with advantages and disadvantages of two methods, the paper suggests that two statistical method can associated with each other in statistical data analysis.
Prediction of Possible Speed and its Application in Highway Alignment Design
Authors: Fan Yong Hua , Yang Shao Wei
Published: November 2012

In view of the shortage of using operating speed to evaluate the safety of highway alignment, we bring forward the use of possible speed. After establishing the computing models of axial, transverse and vertical acceleration, we obtain the methods and steps of predicting possible speed; with that, we describe the standards, methods and steps of highway alignment evaluation using possible speed.To the sections of highway whose alignment parameters are beyond the valuation standards, the solutions are respectively put forward which are amending the alignment parameters or setting the security facilities. Finally, a section of a secondary highway along a river is used as an example.
Study on Transverse Linear Stiffness of Bridge Piers in a High-Speed Railway
Authors: Li Heng , Duan Hong , Li Xiao Zhen , Shan Chun Sheng
Published: November 2012

Based on the theory of vehicle-bridge coupled vibrations, the influence of transverse linear stiffness of double column piers on dynamic response of the train and bridge is investigated. A dynamic model of vehicle-bridge coupled system is established to analyze a high-speed railway bridge by BDAP software (Bridge Dynamic Analysis Program). By comparing the dynamic responses of piers which have different transverse linear stiffness, the characteristics of the relationship between the transverse linear stiffness of pier, the height of pier and transverse dynamic response are summarized, additionally some suggested values for transverse linear stiffness of piers are given to offer guidance for the design and construction of high-speed railway bridge.
Stress Analysis of High Thin-Walled Box Girder Bridge in Chong He Bridge
Authors: Wang Pi Xiang , Yu Ke Xin , Di Jiang
Published: November 2012

Based on the Chong He Bridge as research object, this paper expounds the purposes, methods and analysis results of prestressed concrete continuous thin-walled box girder bridge in the process of cantilever construction. The purpose of the research is to make a reasonable structure which meets the designed stress monitoring and to ensure the quality of construction. The method is to layout stress control points in the main control section and conduct real-time control. The result shows that the beam stress is within the safety range and can predict that the structure meets strength requirements in next stage. The conclusion is that through the data analysis, the results guide the whole process of bridge construction as well as fit the design plan.
The Bridge Wind Tunnel Test Based on the Digital Image Correlation Method
Authors: He Neng , Zhai Peng Cheng , Li Zhi Guo , Fan Ze Min , Yuan Wen Qiang
Published: November 2012

Based on mark points on the surface of bridge pneumatic model, adopting the DIC-Digital image correlation method to handle the pictures captured by CCD Video Camera in the high frequency get the displacement values of the mark points in the time series and thus obtaining the vibration forms of the bridge. The fundamental principles of the DIC-Digital image correlation method and its application were introduced in this paper and the reliability and stability of the method was testified by the comparison to the results measured by the laser displacement sensor
Dynamic Analysis for Steel Bridge Deck Thin Surfacing with Cracks
Authors: Xu Xun Qian , Wang Jian Bo , Chen Jian Ping
Published: November 2012

In order to improve the design method for resisting crack, this paper analyzed the dynamic characteristics of steel deck asphalt thin surfacing with cracks. The model analysis and harmonic response analysis were included to the steel bridge deck thin surfacing. Impact coefficients were calculated with different load cases, road roughness and crack damage. The conclusions can provide a theoretical reference for the assessments of the dynamic failure and long-term performance of the steel bridge deck thin surfacing.
Research on the Load Distribution Coefficient of Cable-Stayed Bridge with Long Cantilever Structure Based on Full-Scale Test
Authors: Li Xiao Zhen , Duan Hong , Li Heng , Ye Wei , Liu Xiao Han
Published: November 2012

This paper is focused on the load distribution problem, which is especially concerned in design phase, for a long cantilever steel-concrete composite cable-stayed bridge with single tower and single cable plane. A large scale full-scale test is performed to make a systematical study on the load distribution coefficient under different conditions. A refined finite element model is gained by FEM software ANSYS to obtain the theoretical results, which are compared with measured data in model test. Finally, a suggested value of the coefficient is drawn through the test result.
Analysis on Dynamic Failure Behaviors of Steel Double-Layer Grids Supported by Circumjacent Steel Columns Used in a Gymnasium with the Function of Earthquake Victims Shelter under Disaster Earthquake
Authors: Zhao Xi , Li Hai Wang , Liu Jing , Ma Yu
Published: November 2012

In this paper, the elasto-plastic dynamic analysis on dynamic failure behaviors of steel double-layer grids supported by circumjacent steel columns used in a gymnasium with the function of earthquake victims shelter under disaster earthquake is carried out under EL-centro wave with SAP2000, and the appraisal results on their anti-failure performances are presented under strong earthquake action based on the plastic-hinge theory. In the analyses, the geometric and material nonlinear effects are considered simultaneously based on the plastic-hinge theory. The plastic development level of the rod, the deformed shape and the failure type and the ductility are estimated by plastic hinge principle. The results show that: Along with the growth of the seismic wave peak acceleration (shorted as PGA), structure developed from elastic into the elastic-plastic. The failure model of the structure under the earthquake wave action is due to overall elasto-plastic instability of double-layer grids. When the structure reached its failure critical limit, the development of the plastic hinges is sufficient and 24.5% of the rods enter into their plastic stage; The ratio of its maximal failure node vertical displacement and its short span is 1/51, The ratio of its maximal failure node horizontal displacement and its columns is 1/49; Its critical failure PGA is 771gal, which is 1.9 times more than the official seismic fortification level of 8 degree (major earthquake, 0.2g) and can be served as earthquake victims shelter in the area of 8 degree seismic fortification; Its displacement ductility coefficient is 7.6,which shows the structure owns good energy dissipation capacity.
Energy Response Spectra of Single-Mass Bi-Degrees of Freedom Systems for Hard Soil Site
Authors: Wang Feng , Li Xin Le , Yi Ting Hua
Published: November 2012

The traditional energy response spectra depend on the single-directional earthquake excitations and two dimensional dynamic analyses, in which the imbalance and coupled characteristics of multi-dimensional responses of structures are not considered. So, the energy spectra of constant ductility facotors are developed by considering the single-mass bi-degrees of freedom systems subjected to perpendicular bi-directional earthquake motions. The restoring force rule of single-mass bi-degrees of freedom systems is assumed as two dimensional yield-surface plasticity function. The relative energy spectra for input energy, hysteretic energy, kinetic energy and damping energy are presented and analyzed based on 34 pair earthquake motion records of hard soil site. Analytic results show that the energy spectra for hard soil site have their own characteristics, and the spectral forms and values are affected strongly by vibration period, ductility factor and period ratio of single-mass bi-degrees of freedom systems.
The Application of Mode-Superposition Response Spectrum Method in Seismic Calculation of the Boiler Steel Structure
Authors: Li Shu Wei , Zhao Wen , Jin Jia Xu
Published: November 2012

The boiler steel structure is the main parts of the boiler, its stability directly determines the normal operation of the boiler and the security of the surrounding environment. For analyzing the boiler steel structure, first respectively using matrix displacement method, energy method and the empirical formula method to calculate the periodic of the boiler steel structure; then using the bottom shear method and the mode-superposition response spectrum method to calculate the shear and the axial force of the boiler steel structure in same situation, and through comparing the results to gain the correction coefficient of the mode-superposition response spectrum for the engineering practice and discussing the calculation of the boiler steel structure under earthquake using mode-superposition response spectrum method. Providing the theoretical basis for the seismic design, the reinforcement and the maintenance of the boiler steel structure.
Research about Rolling Friction Pendulum Seismic Isolation System on Ellipse Track
Authors: Pan Jiang , Ge Nan , Yao Li Ting
Published: November 2012

A theoretical analyzing approach about a class of seismic isolation system RFPS (Rolling Friction Pendulum System) is presented.. It starts from the Lagrange equation in multiply body dynamics. This system consists of a roller which is placed in the vicinity of two ellipse concave slides. Computation results for ellipse slide show that it has the three kinds of necessary functions required for an effective isolation system. The relatively long vibration period provides the necessary isolation capability, the gravity provides the reposition capability, and the friction couple, formed with the rolling friction forces at the contacting surface on the top and bottom plate respectively, provides the energy dissipation capability. The evaluation results for a practical building model shows that RFPS has a satisfactory seismic isolation effect.
Discussion on the Geometric Methods to Calculating the Fault Complexity Coefficient
Authors: Wang Jian Guo
Published: November 2012

Lots of faults exist in rock mass. Acconding on the course of quantitative analysis of fault complexity in mine and modern civil engineering at present, single fault complexity coefficient represents various geologic facts, and its value is less than the fact. Based on the evaluation of sheer incline area ratio and strike-slip fault area ratio about former research, measure fault complexity take an inclined fault interval multiply by the sum of extension length and ratio of numerical statement area. By geometric analysis of geological objects, this paper put forward geometric model which represents geological facts in truth. The results show that expression educed from the model has no multiplicity, is transpicuous and convenient for popularizing.
The Cable-Stayed Bridge with the T - Structure Collaborative System Bridge Seismic Response Analysis
Authors: Yu Bao Chu , Zhang Da Yong , Gao Shao Xia , Tang Xiao Cheng
Published: November 2012

The main bridge of Guangdong jinma which is double cable planes concrete single tower cable-stayed bridge and T- rigid frame cooperative system,and causing great concern to the project owing to the practice successfully[1,2,3,4].This paper analysis Jinma Bridge with response spectrum method of seismic response in accordance with the objectives of the three standards of seismic resistance requirements .In order to ensure the calculation accuracy,before the previous 120 vibration mode superposition should be taken by adopting CQC（Complete Quadratic Combination）method in calculation of the response spectrum.
Seismic Performance on Reinforced Concrete Frame Joints of Open Set Corner Floor
Authors: Chen Hai Bin , Ge Nan , Zhang Yan Pu
Published: November 2012

Quasi-static analysis of in-situ reinforced concrete frame joints is done by using finite element software ADINA. The calculation results of the ordinary beam-column joints and the surrounding floor located Corner joints are compared. It is shown that near the beam ribbed slab reinforcement stress significantly increases with the loading displacement increasing, indicating that the floor enhance the flexural capacity of beam. On the conditions of no influence the joint strength, floor set corner can be partially weakened the capacity of the beam flexural, and reinforcement of beams yield significantly in advance. When the beam reinforcement yield, the column of concrete cracks have also been reduced. Meanwhile, the beam-end and column-end plastic hinge appears increase the time interval, so that the joints are closer to the characteristics of the beam hinge mechanisms by the earthquake damage.
Laboratory Study and Evaluation of the Loess Liquefaction under Random Seismic Loading
Authors: Wang Jun , Wang Lan Min , Ma Hai Ping , Wang Qian , Wang Ping , Fan Bing
Published: November 2012

By using the DSD-160 dynamic triaxial apparatus, liquefaction experiments under random seismic loading of the saturation original samples from a passenger rail line which located in the loess tableland in china was tested. Based on the test results, connected with the forecasting method of the liquefaction test under random seismic loading and the results of seismic hazard analysis, the liquefaction potential of the saturation loess from different regions in the passenger rail line is distinguished. Moreover, the predictions include 50 years probability of exceedance 10% and 2%of the loess liquefaction potential of the sites mentioned above is obtained.
Progress in the Seismic Strengthening of RC Frame Connections
Authors: Wan Li Hua , Zhao Guo Dong , Li Lin Lin
Published: November 2012

Frame connections imminently need to be strengthened for deficient seismic-resistance in early time. The paper presents research results of strengthening connections through concrete jacketing, bonding steel plate, prestressing, wrapped steel and FRP by scholars in home and abroad, contrasts their strengthening effect and gives the future research aspect.
Simulation of the Seismic Response of 2D Sedimentary Basin with Hybrid PSM/FDM Method
Authors: Yan Wu Jian , Wang Yan Bin , Shi Yu Cheng
Published: November 2012

Abstract: In this paper, we simulated two-dimension numerical on the strong ground motion in Lanzhou basin through the hybrid scheme based on the pseudospectral method (PSM) and finite difference method (FDM). We base on a focal of 20 km deep and a profile of 5 layers is used as model to analyze the site response and the peak displacement of strong ground motion. The results show that the hybrid PSM/FDM method for seismic wavefield simulation combines with advantages of PSM and FDM and makes up for the disadvantage of them, so this method can process well the calculation of the discontinuous medium surface, then the calculation accuracy is similar to PSM. Through the wavefield simulation it is known that the peak ground displacement (PGD) of the vertical is larger and the influence of surface wave at the basin edge is more obvious than the horizontal.
A Method to Determine the Warning Value of the Opening of Concrete Dam Crack Based on the Analysis of Time-Effect and the Low Probability Method
Authors: Jing Ji
Published: November 2012

During the long-term operation of concrete dam, the cracks in concrete dam might have propagated. Aiming at this situation, based on the comprehensively consideration of the evolution and abnormality situation of concrete dam crack, a method to determine the warning value of the opening of concrete dam crack was proposed. First, the time-effect of crack opening was extracted and its variation law was analyzed, according to this, the occurring time of the unstable propagation of crack was determined. Then, the warning value of crack opening after the last propagation of crack was determined by use of the low probability method. Apply this method to analyze the measured data of a concrete dam crack; the warning value of crack opening was determined successfully; this shows that this method has certain application value.
Control of Artificial Recharge on Foundation Pit Deformation due to Dewatering
Authors: Yuan Hua , Hong Yan
Published: November 2012

In this paper, the currently available, feasible controlling measures for the deformation of foundation excavation and its surrounding environment are summarized systemically, which is mainly embodied in pit collapse, adjacent building differential settlement as well as underground pipeline cracking. Then first from the two aspects: artificial recharge used as prevention method and management measure separately, the paper illustrates the control principle, operation method and matters needing attention during artificial recharge. In addition, the difference between pumping well and recharge well are discusses. The research results will provide direction for the deformation control of deep foundation excavation and the operation of artificial recharge.
Temperature Induced Cracking Analysis for Lushui Pier Using LEFM
Authors: Cheng Jing , Chang Xiao Lin , Li Tong Chun
Published: November 2012

The cause of the concrete pier cracks of Lushui Puqi Hydraulic Hinge in China is studied by FEM (finite element method). The transient temperature field and thermal stress during thermal shock are simulated, and the sudden decrease of air temperature is concluded to be the main cause. Then the probabilities of crack propagation during thermal shocks are discussed in detail based on LEFM (linear elastic fracture mechanics), the results show that cracks will propagate during another thermal shock of 10°C or more decrease. Mode I Stress Intensity Factor KI is adopted to describe and evaluate the concrete crack characters. Further discussion is made on the influence of time, temperature decrease and crack depth.
The Research on the Relation between Flexibility Coefficient and Buckling Stability of High Arch Dam
Authors: Li Hui , Wang Zheng Zhong , She Xuan
Published: November 2012

As a result of many high arch dams that are building and would be built in the south-west and north-west of China, arch dam is a kind of compressed thin buckle, not only effect by tension, but also by deformation. Thinner dam body with usage of increased levels of concrete and optimum designing, the local regions of high arch dams approach thin shell structure，which will lead to the structural buckling. Base on the above present condition, this paper would establish a series of generalized high and thin arch dam models whose height are 240m, and make theoretical analysis based on one of the crown- cantilever method- differential method for them, which attempts to provide a new method for the" critical flexibility coefficient ". At last, this paper would provide the relation between coefficient and buckling stability of high arch dam
Numerical Analysis on Ground Displacement at Mined-Out Area of Yuecheng Reservoir Project
Authors: Duan Shi Wei , Xu Xian E
Published: November 2012

Coal mining activity has potential hazards to the safety of the Yuecheng Reservoir Project due to ground subsidence and water seepage. Mohr-Coulomb constitutive model was built and FLAC/FLAC3D program was used for numerical simulation analysis of the ground deformation response with mining of coal, then, displacement characteristics of the roof strata and distribution of overlying stress field were brought out, and the scope of water transmitting fracture zone was calculated.
Study on Stress of Closed Cut-Off Wall in Earth-Rock Dam Reinforcement under Different Engineering Conditions
Authors: Gao Jiang Lin , Chen Yun Xiang
Published: November 2012

Closed concrete cut-off wall has been widely used in the reinforcement projects of earth-rock dam. However, the research on the cut-off wall was rare. In order to discuss the stress state of the wall under different engineering conditions, a coupled numerical model was established by considering coupled interaction, including contact between wall and dam, and coupling of stress and seepage. Taking the earth-rock dam which built on common foundation for example, the stress distribution of the wall and influencing law of different factors were mainly researched, including elastic modulus of the wall, deformation modulus of the dam filling materials, permeability coefficient of the dam foundation, etc. The conclusions had reference significance for the application and design and calculation method of concrete cut-off wall in the reinforcement projects of earth-rock dam.
Study on Flow Velocity Field of Local Scour around the Pier Protected by the Sediment Storage Dam
Authors: Zhao Hai Jing , Li Dan Xun , Wang Xing Kui
Published: November 2012

Aimed at the representative project which is protected by the downstream sediment storage dam, three dimensional flow velocity field in local scour area around the separate bridge pier via physical model test was studied. The influences of shaping the eroded pit caused by the velocities in different directions were analyzed. The distribution results of flow velocity field in local scour pit near the pier protected by the sediment storage dam, deduced from the paper, will provide references for the defensive design of bridge projects.
Numerical Analysis of Passive Pile due to Excavation
Authors: Sun Yue , Wang Zhi Yun , Chen Yue Nan , Jiang Yun Shen
Published: November 2012

An elasto-plastic total stress finite-element computational model is established in two dimensional space to study pile response due to excavation-induced soil movement on the basis of the general-purpose finite element software ABAQUS. And the soil is assumed to be a uniform normally consolidated clay layer. Influences of various parameters including undrained shear strength of soil, excavation depth, strut stiffness and distance from excavation on pile response are investigated. The results indicate that the excavation-induced soil movement is critical for adjacent piles and increasing the undrained shear strength of soil and distance from excavation face would be helpful to control passive pile responses.
Flood Risk Map Analysis Based on Dam-Break Simulation
Authors: Wang Xiao Ling , Zhou Long , Sun Rui Rui
Published: November 2012

The flood risk map is useful to make a regional flood emergency plan and analyze the dam-break flood risk. A three-dimensional mathematical model is applied to simulate the floods evolution with consideration of the dam-break process and the complex boundary condition synthetically, and the finite volume method is used to get a discrete solution. The flood evolution process of Dongwushi reservoir in the instantaneous collapse conditions is taken as a case, and the flood risk map is obtained based on the results of calculation.
Use of Prior Information for Calibration of River Roughness
Authors: Chen Yi Fan , Wang Chuan
Published: November 2012

River roughness calibration usually is an underdetermined model for lack of hydrological information, and its calibrated results may deviate from the true solution seriously. Using prior information is an effective way to regularize inverse problems, which can make the calibrated results reasonable and improve the stability of numerical calculation. A robust model, which takes account of river roughness smooth matrix and error minimization, is developed on the basis of the prior information that the spatial distribution of river roughness is smooth. In the computing example of a river network, cases are tested about the uniqueness of solution, numerical stability, and reliability. The results show that the present model can calibrate river roughness effectively with high numerical stability and reliable results.
Influence of Perforation Parameter on Crack Initiation and Extending of Hydraulic Fracturing
Authors: Jiang Min Zheng , Li Yang , Zhang Yi Ming , Jiang Tian Xue , Liu Ming Xing
Published: November 2012

Widespread problem in hydraulic fracturing of low-permeability reservoir is difficulty of crack initiation of fracturing, high initiation pressure of fracturing put forward higher requirements of fracturing equipment. Low-permeability reservoir for the study, in the fluid-solid coupling conditions, established a low-permeability reservoir perforation mechanical model of stress, using numerical solution techniques, consider the dynamic effects, we can achieve the stress distribution at different stages: drilling, well cementation, perforation and fracturing in low-permeability reservoir. With rock tensile fracture criterion can determine the initiation location and initiation pressure. The results show that the lower the degree of pollution in perforating hole, the smaller the pressure from the crack initiation as well as the higher the degree of pollution in perforating hole, the larger the pressure from the crack initiation. Orientation, diameter and depth of perforating hole effect on crack initiation and extension are more significant.
Research on Identification of Comprehensive Pipeline Headroom in Certain Area
Authors: Zhao Qin , Bai Guo Liang , Hei Xin Hong , Zhang Peng Fei
Published: November 2012

The comprehensive pipeline is a kind of important facilities and equipment and the key to normal operation in metro station, and the certain design requirement of various pipelines’ headroom in specific spatial region need to be met. As a technology centralized upon information and based on three-dimensional mode, BIM technology can express three-dimensional model of metro comprehensive pipeline imaginatively, provide the spatial topological relations among pipelines and relevant detecting calculations. In this paper, the necessity of identification of headroom of metro comprehensive pipeline is deeply analyzed, and then the article designs identification algorithms of headroom of metro comprehensive pipeline according to BIM technology. This algorithm can detect the pipelines which not meet the design requirements of headroom on BIM platform efficiently, thus we can improve design efficiency and quality and liberate labors so that designers can be engaged in more complex design work
Magnetic Water Treatment to Inhibit Calcium Carbonate Scale Deposition in the Drainage System of an Old Tunnel in Seoul, South Korea
Authors: Yee Eric , Lee Jongh Wi , Lim Dae Sung , Chun Byung Sik
Published: November 2012

Drainage inlets at the Namsan #3 traffic tunnel in Seoul, South Korea were found to be clogged with calcium carbonate scale deposits. Officials were concerned the clogged drains would further stress the already deteriorating traffic tunnel and wanted to see if there were any practical and economical solutions in removing or preventing scale deposits. A tunnel drainage simulator was constructed to determine the feasibility of using magnets to inhibit scale precipitation and deposition. Test results from the simulation show 6.0 and 4.4 g of deposited calcium carbonate in pipes inclined at 2° and 5° respectively, while magnetically treated water resulted in 10.8 and 4.3 g of deposited calcium carbonate in pipes inclined at 2° and 5° respectively. Calcium carbonate scale samples from the tunnel drainage test underwent x-ray diffraction analysis and showed the magnetically treated water to precipitate more aragonite. The solubility product and crystalline structures of calcite and aragonite are able to help explain tunnel drainage test results and suggest water flow velocity to be a potentially important factor in calcium scale inhibition if magnets are used.
Research on Energy-Saving of the Pebble Thermoregulation Greenhouse
Authors: Shi Yu Liang , Chen Ming Dong , Wang Fu
Published: November 2012

The pebble thermoregulation system in greenhouse bottom corner is put forward according the characteristics of greenhouse structure and higher energy consumption. The indoor temperature of the pebble thermoregulation greenhouse is monitored in the course of experiment and the temperature change law of greenhouse bottom corner and greenhouse middle is analyzed and heat storage of pebble thermoregulation system is calculated. The results showed that heat storage of pebble thermoregulation system is higher, it is has important theoretical and realistic significance for greenhouse heating in winter.
Study on Temperature Distribution Regularity of Pebble Thermoregulation Greenhouse
Authors: Shi Yu Liang , Chen Ming Dong
Published: November 2012

According to the characteristics of non-uniform temperature distribution in the seeding greenhouse, a pebble thermoregulation system in the bottom corner of greenhouse was put forward. The changes regularity of indoor greenhouse temperature with outdoor weather conditions was studied according to monitoring the date of experimental greenhouse, which was a pebble thermoregulation greenhouse and contrast greenhouse with same structure, such as indoor temperature and out temperature, etc. The results showed that temperature distribution between greenhouse bottom corner and greenhouse middle is uniform and the temperature difference is less than 1°C.
Characteristics of Gas Transport within Uniaxial Compression of Granite Sample
Authors: Wang Chun Guang , Li Chaojun , Hu Xueqiang , Li Bingqian
Published: November 2012

The physical processes triggering the fluid flow within the stressed rock are highly complex and not fully understood. The granite sample obtained from Creighton mine, Canada, was subjected to the temperature-pressure effects using a special rock mechanic testing machine equipped with a high precision gas monitor. It is shown that when the sample approached to the peak stress during the uniaxial compression test, the connective cracks instantaneously occurred accompanied by a swarm of AE activities, which suddenly decrease the fluid pore pressure. This change can be able to drive the gas back to the newly emerging crack due to the formation of gas pressure gradient within the damage zones. It is indicated that the different permeabilities among the zones can dominate the suction-exhaust proceeding of pore fluids within rock mass. Beyond the volumetric strain at null, the deformation of the stressed rock leads to a reversely change in pore pressure of closed pores. The feature for the gas emission determined by the changes in pore structure of rock is also discussed and analyzed.
Physical-Rule Based Adaptive Neuro-Fuzzy Inferential Sensor vs. GA-BP Based Prediction Model in Indoor Temperature Predicting
Authors: Huang Liang , Liao Zai Yi
Published: November 2012

The previous research on temperature prediction presented different approaches which are physical-rule based adaptive neuro-fuzzy inferential sensor (ANFIS) model and GA-BP (genetic algorithm back propagation) based model to estimate the average indoor temperature in the building environment. Their good prediction performances improved energy efficiency of district heating system and indoor comfort ratio. However, either of these two models has its drawback in a certain condition. In this paper, the two prediction models are reviewed and evaluated by three performance measures (RMSE, RMS, and R2). Their limitations are discussed and potential solution is proposed.
Improvement of Proximal Support Vector Machine and its Application to Enhance Antifreeze Heat Transfer Capability in Ground Source Heat Pump System
Authors: Wang Jiu Hai , Yan Man Fu
Published: November 2012

To solve the problem of enhancing the heat transfer capability of antifreeze mixture in a ground source heat pump system, the existing proximal support vector machines [1] was updated into a weighted Proximal Support Vector Machine (PSVM) model. Also, a new classification method of mixed antifreeze heat transfer capability was given in the paper by analyzing antifreeze [2] heat transfer capability of the ground source heat pump system and applying the weighted PSVM mode.
The Coupled Heat Conduction & Advection Model for Ground Heat Exchanger and its Application for Utilizable Resource Amount Calculation in Soil
Authors: Fan Rui , Gao Yan , Long Wei Ding
Published: November 2012

Following the wide application of ground source heat pump (GSHP) system, especially for large area ground heat exchanger (GHE), it is really necessary to have a standard calculation or assessment method to estimate the utilizable resource amount in soil around GHE. As for the GHE area, the soil works as a thermal storage actually which means it is heat gain in summer to meet the heat demands in the coming winter, and the cool energy gain in winter to be used for next summer air-conditioning. So it is really necessary to know the utilizable resource amount for better design of GSHP system and then the highly efficient operation of the system too. Hereby, a coupled heat conduction and heat advection model is introduced to simulate the performance of ground heat exchanger. Thus we can see the importance of utilizable resource amount estimation method. The reasonable resource amount estimate method is good for the scientific design, normal utilization, and high-efficient operation of GSHP system.
Natural Dam Break Forecasting by Use of DamBrk Model
Authors: Dang Chao , Chu Na Na , Ding Yu
Published: November 2012

The Dam Break model (DamBrk) developed by Fread was the most famous parametric dam break forecasting model with flexible inputs, and typically widely used for embankments or other man-made dams failure. The paper aims to discuss the parameter selection and calculation for natural dams, which are used as necessary input in The DamBrk model. And then the Tangjiashan landslide dams formed in 2008 Wenchuan earthquake is utilized to test the reasonability of DamBrk model. Outcomes shows that computed outflow volume through breach coincides with the observed values in magnitude when appropriate breach times be assumed. The methods put forth herein can also be helpful for the early warning and human evacuation of other natural dams.
Horizontal Pillar Stability Evaluation and Instability Risk Prediction of Jinchuan No.2 Mine Area
Authors: Liu Zeng Hui , Gao Qian
Published: November 2012

In order to study the horizontal pillar stability of Jinchuan No.2 mine area, the 13 factors and three levels of the numerical calculation orthogonal pilot program was devised. We had required the evaluation function of the 3 index which was averaging stress of horizontal pillar, Shear stress of horizontal pillar, Failure ratio of horizontal pillar, and used reliability theory to analyze reliability and risk prediction of the horizontal pillar stability. The results showed that averaging stress of horizontal pillar instability risk is 5.57％, shear stress of horizontal pillar instability risk 4.37％, failure ratio of horizontal pillar instability risk 8.222％, The stability reliability of horizontal pillar is 82.88%, and the instability risk probability 17.12%.
An Implementation of 3D Landslide Geological Modeling and Visualization
Authors: Jiang Ting Yao , Cui Le Le , Li Jia Heng
Published: November 2012

Three-dimensional (3D) geological modeling and visualization of landslide is very important for landslide monitoring and stability evaluation. Unfortunately there have not been very efficient methods to realize this modeling and visualization process currently. An implementation of 3D landslide geological modeling and visualization based on a hybrid data structure of TIN and GTP is introduced in this paper. The proposed implementation method includes three sections: pre-processing terrain data for known or history data; 3D modeling of landslide terrain surface, slip surface and geological structure surfaces; construction of 3D landslide geological model and 3D visualization of landslide model through java 3D API. The introduced method contributes to a new approach to landslide research.
Study on Highway Intelligent Travel Service Improvement Using Location-Based Service
Authors: Wang Zhao Nan
Published: November 2012

This paper comprehensively analyses the current condition of highway travel services problems at first, and then introduce the theory and background of an emerging technology------LBS (Location Based Service). It discusses the possible methods of using LBS to solve the existing problems in highway navigation and other travel services. Taking the application of LBS applied in urban transportation for reference, this paper proposes the LBS highway solutions with the consideration of characteristics of LBS and highway. Finally, the key issues of LBS application in traffic Navigation are summarized.
A Semi-Automatic Algorithm on Extracting Road Networks from Airborne LiDAR Data
Authors: Li Feng , Cui Xi Min , Yuan De Bao , Hu Kai Long , Xu Wan Yang
Published: November 2012

Airborne LiDAR (Light Detection and Ranging) is a powerful remote sensing measure to derive 3D coordinates from terrain surface. Automated or semi-automated road networks extraction from laser point clouds has been a challenging work during last few decades. In this paper, combining intensity with height information of point clouds, initial road point class is discerned using few seed points and subsequently smoothed throughout filling holes technology and morphological open operations. The skeleton of road networks is acquired by virtue of image thinning method and further eliminating short road burrs with length criteria. These center points of road are tracked and connected into vector line segments. By simplifying line nodes, road network can be formed in accuracy of which completeness is 79.8% and correctness is 79%. The virtues of this algorithm enables efficiently reduce errors brought by parking lots.
Deformation Module Dynamic Inversion of Xietan Sewage Treatment Plant Slope when Exposed to Reservoir Water Level Fluctuation Based on Fluid-Solid Coupling Theory
Authors: Wang Xing Lin , Zhang Zhen Hua , Sun Qian Cheng , Li Shao Jun
Published: November 2012

This paper selects the Xietan sewage treatment plant slope as research object, used the fluid-solid coupling finite element analysis software (ABAQUS) and intelligent displacement back analysis method to dynamically inverse the deformation module of rock and soil of the slope when exposed to water level fluctuation. The results show that the calculation displacement values of measuring point which based on the inversion method is very close to that based on field measurement, which indicates the intelligent displacement back analysis method is suitable to dynamically inverse rock and soil physical and mechanical parameters of slope when exposed to reservoir water level fluctuation.