bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Deformation Prediction of Coastal Roads Based on Grey Model
Authors: Wu Ming Bai , Xiong Xiao Bo , Fan Zhi Qiang , Zhu Xiao Qing
Published: September 2011

As China's economic construction and social development, projects of roads , railways and other transport infrastructure are also increasing. The safety and efficiency and the quality of life of the road works in the construction and operation periods is closely related with the foundation. Based on the systematic analysis of various factors affected the subgrade deformation, this article makes the main factors to Subgrade Deformation, and the prediction model GM (1, 1) based on gray system theory has been used to build a model on the embankment settlement of coastal highway. Then to predict with the data of highway subgrade. Comparing the model forecasts with the measured data of practical engineering, it shows that the model could reflect the laws of subgrade deformation which has some practical reference value.
Parametric Modeling for Globoidal Cam Based on CATIA/CAA
Authors: Zhang Guang Guo , Chang Zhi Bin , Liu Hai Tao
Published: September 2011

The design and machining of globoidal cam is difficult,because the shape of working surface is complex,and the curved surface of its space is undevelopable. Based on the above reasons,we proposed the parametric Modeling method for globoidal cam based on CATIA/CAA. Through the secondary development of CATIA,we realized the parameterized modeling of globoidal cam using the modelling mothods based on the feature model,it made the design process simplified,improved the efficiency of design,provided a new solution for the design of globoidal cam.
Optimization of Processing Parameters for Shell Products Based on Taguchi Method and DOE Technology
Authors: Li Chun Bo , Fu Xue Long
Published: September 2011

An Orthogonal experiment was carried out combined with MPI technology and Taguchi method in order to investigate the effect of parameters, the temperature of the melt and mold, injection duration, packing pressure and duration on the quality of barrel plastics. The optimum parameters to get a minimum volumetric shrinkage and sink index was also finally obtained, that is, melt temperature at 190°C, mold surface at 50°C, injection duration at 5s, packing pressure at 70 MPa with 20s duration.
Research on Optimization Algorithm Applied in Plate Rolling Schedule
Authors: Chen Na Na , Fei Qing , Hu Hao Ping
Published: September 2011

The paper studies the optimization design of rolling deformation schedule on plate mill. In order to ensure to play equipment ability full and control the precision of flatness, optimization mathematical model of flatness passes is firstly given. Then, the objective function is formulated in accordance with the actual production conditions, and the flatness constraint conditions are confirmed based on equipment and technical requirements. Finally, GA is applied in the optimization calculation of rolling schedule and a lot of simulation experiments are conducted with actual data. Analysis and comparison of optimized schedule with the existing schedule were offered. It is seen that the performance of the optimal rolling schedule is satisfactory and promising and the design is feasible and promising.
The Ground State Energy of the Electron in Quantum Ring Induced by the Rashba Effects
Authors: Li Hai Feng , Qimuge Wu Yun , Liu Xiao Lei , Eerdun Chao Lu
Published: September 2011

Influences of Rashba spin-orbit interaction(SOI) effects on the ground state energy of the electron in quantum ring at zero fields are studied by means of the perturbation method. Numerical calculations for CdF2 ring are performed and the results show that the Rashba SOI makes the ground state energy of electron split into two branches, which are induced by the spin-up state and spin-down state, respectively. Two branches splitting energy increases oscillatorily with increasing the inner radius of quantum ring and decreases oscillatorily with increasing the outer radius of quantum ring. The largest Rashba spin splitting energies in the process of oscillation-increase and oscillation-decrease are 11.91meV and 13.97meV, respectively. These data and results are helpful to design and develop spin field effect transistor, spin light-emitting diode, spin resonant tunneling device, etc.
Position Sensorless Control Based on Augmented Extended Kalman Filter for Permanent Magnet Linear Synchronous Motor
Authors: Lu Hua Cai , Jiang Ming , Wei Li Sheng , Liu Bing You
Published: September 2011

In order to achieve position sensorless control for PMLSM drive system, speed and position of the motor must be estimated. A novel sensorless position and speed estimation algorithm was designed for PMLSM drive by measuring terminal voltages and currents. That was state augmented extended Kalman filter (AEKF) estimation method. The resistance of the motor was augmented to the state variable. Then, the speed, position and the resistance were estimated simultaneously through extended Kalman filter (EKF). The influence of the resistance on the state estimation results could be reduced. As well as giving a detailed explanation of the new algorithm, experimental results were presented. It shows that the AEKF is capable of estimating system states accurately and reliability, and the proposed sensorless control system has a good dynamic response.
Properties of Elements in Fault Delivering in Power System
Authors: Li Jiang Hua , Hu Juan
Published: September 2011

This paper presents a novel method for Properties of Elements in Fault Delivering in power system. It is based on the properties of elements in fault delivering. the upstream fault indices of all nodes in sub-network also can be calculated. By synthesizing the upstream and downstream reliable indices, the reliable indices of all nodes in the sub-network can be obtained. the proposal method not only has the same effect but also save computing time. The results of simulation applying the proposed method to test system adequately showed that this method is effective
3-D Numerical Simulation and Analysis on V-Cone Flowmeter Based on LES Method
Authors: Zhu Wei Bin , Meng Jin Long , Yin Zhao Qin
Published: September 2011

The rear pressure measurement position of V-cone flowmeter is in the complex vortex structure area after fluid around the cone. The non-uniformity of the fluid field will influence the measurement precision of V-cone flowmeter. Large eddy simulation (LES) has been used to study the V-cone flowmeter’s 3-D flow field structure with different Reynolds number in this paper. The better fluid area information can gain by this way. The results show that the values of discharge coefficient (Cd) obtained from LES are more close to the experiment data than the values obtained from k-ε model. Different turbulence intensity with different Reynolds number effects the velocity distribution in the V-cone flowmeter’s flow field. When Reynolds number equals to 20000, the flow field within 8d distance from V-cone tail should keep from being disturbed while the flowmeter under working condition. The non-interfering distance from V-cone tail flow field increases with the Reynolds number raising. These analysis results can offer optimizational information for V-cone flowmeter performance and testing method improvement.
A Light RSSI-Based Three Dimensions Location Estimation Algorithm for Indoor ZigBee Network
Authors: Xu Bin , Yu Zheng , Ge Yu Jia , Han Pei You
Published: September 2011

Received signal strength indication (RSSI) is one of the primary location techniques, which has been popularly used in ZigBee wireless sensor network. In this paper, the authors suggest to use RSSI-based technique to design a three dimensions location and finally realize valuables guardian system within an intelligent environment supplied with indoor ZigBee network. Several mobile nodes can be freely attached to the valuables and the movement of the nodes will be monitored by the system in period. Hierarchical alarm mechanism could be issued when some abnormal movements have been identified according to some pre-defined rules. The misstatement rate is low in the experiment.
Using Evolving Fuzzy Models to Predict Crude Oil Distillation Side Streams
Authors: Macías-Hernández José J. , Angelov Plamen , Zhou Xiao Wei
Published: September 2011

Prediction of the properties of the crude oil distillation side streams based on statistical methods and laboratory-based analysis has been around for decades. However, it is difficult to identify, control or compensate the dynamic process behavior and the errors from instrumentation for an online model prediction. The objective of this work is to report an application and a study of a novel technique for real-time modelling, namely eXtended Evolving Fuzzy Takagi-Sugeno models (xTS) for prediction and online monitoring of these properties of the refinery distillation process. The results include the online prediction of Soft Sensors for distillation of Naptha and Gasoil Side Streams. The application predicts the quality of the side stream evolving its fuzzy structure and cluster parameters.
Numerical Simulation of Heat and Moisture Transfer in System of Human-Clothing with Phase Change Materials-Environment
Authors: Li Feng Zhi , Wang Peng Fei , Li Yi
Published: September 2011

A model of heat and moisture transfer in human-clothing with PCM-environment system is developed. In the model, the improved 25-node model is used for simulating human thermo- regulation, and the coupled heat and moisture model is applied to the PCM’s clothing. The model predictions and experimental data are compared. Also, the influences of the PCM on human skin temperature and sweat accumulation are predicted. The results are helpful to design of thermal functional clothing.
A Method to Compute Siphons Based on Matrix Manipulation
Authors: Chen Xue Peng , Zhao Liang Xu , Lin Shan Fa , Wu Wen Hui
Published: September 2011

As a structural object of Petri nets, siphons are significant in the analysis and control of deadlocks in a Petri net. However, some existing siphon computation methods are quite time-consuming. In this paper, based on incidence matrix manipulation, a new method is proposed to compute a set of siphons in a class of Petri nets called systems of simple sequential processes with resources (S3PR). The proposed method consists of two algorithms: 1) computation of an unmarked maximal siphon and 2) obtain minimal siphons from an unmarked maximal siphon. A flexible manufacturing systems (FMS) example is used to illustrate the proposed method.
Expressions for the G-Drazin Inverse of Additive Perturbed Elements
Authors: Guo Li , Liu Yu Jing
Published: September 2011

To study the properties of the generalized Drazin inverse in a Banach algebra, an explicit representation of the generalized Drazin inverse under the some conditions. Thus some results are generalized.
Design of Pressure Sensor in Common Rail System by ANSYS Tools
Authors: Ye Feng , Wang Zhong Ming
Published: September 2011

A pressure sensor used in the Common Rail System is designed to monitor the oil pressure changing form 0 to 200MPa in the temperature from -40 to 130°C. It is composed of elastic cell, strain gage and signal processing circuit. Elastic cell produces liner strain with the oil pressure; strain gage transforms this strain into electrical signal that is enlarged and processed by signal processing circuit. To describe the relation of oil pressure with the strain, the stress distribution and strain of elastic cell with different shape is simulated, applying ANSYS tool in the 200MPa pressure. Then, an acceptable shape is produced and tested. It has the similar features with simulated result and works well.
Reliability Assessment of Power System Using Importance Sampling Technique Based on Layer Optimization Simulation
Authors: Wang Bin
Published: September 2011

An improved importance sampling method with layer simulation optimization is presented in this paper. Through the solution sequence of the components’ optimum biased factors according to their importance degree to system reliability, the presented technique can further accelerate the convergence speed of the Monte-Carlo simulation. The idea is that the multivariate distribution’ optimization of components in power system is transferred to many steps’ optimization based on importance sampling method with different optimum biased factors. The practice is that the components are layered according to their importance degree to the system reliability before the Monte-Carlo simulation, the more forward, the more important, and the optimum biased factors of components in the latest layer is searched while the importance sampling is carried out until the demanded accuracy is reached. The validity of the presented is verified using the IEEE-RTS79 test system.
Optimization Method of Hoisting Points Schemes Using Strain Energy Criterion
Authors: Li Shun Guo , Li Hui
Published: September 2011

The optimization method of hoisting point’s schemes using strain energy criterion was studied in this paper. Firstly, the finite element model of complex steel truss hoisting was established and optimization analysis of hoisting point’s schemes for complex steel truss hoisting using strain energy criterion was accomplished. The calculation code which can make finite element analysis and optimization analysis of lifting point’s schemes based on strain energy criterion automatically. Then, lifting point’s schemes of complex steel truss hoisting were analyzed with calculation code mentioned above. The results indicate that, the optimization index using strain energy criterion is just strain energy criterion which is a more comprehensive and unidirectional index. Optimization analysis based on strain energy criterion changes optimization analysis of the lifting points schemes for complex steel truss hoisting from multi-target optimization into single-target optimization. The case study shows that this method is practicable and reliable and have good application prospect in hoisting points schemes optimization analysis with application to complex steel truss hoisting.
Research and Application of Computer Aided to the Automobile Outline Design
Authors: Zheng Ze Feng , Li Jiu Xi
Published: September 2011

With the sharpness of market competition, the design of automobile outline becomes more and more important. By far, no systematic method can direct designers to carry out creative design orderly. In fact, most of the instances are created by designers’ cerebrum independently. The rise of the evolution computation provides us a new approach for conceptual creative design; therefore, it has become one of the most important techniques for computational and creative design. This paper pays more attention to the computer aided environment in the automobile outline design, proposes the automobile outline modularization design method and classifies component base into two categories. This method stores the data in the format of XML, which can save great memory and amount of rebuild component time.
The Research of Data Mining Based on Fuzzy Cluster
Authors: Fang Fu Gui
Published: September 2011

Fuzzy clustering analysis is an important branch of unsupervised pattern recognition. Studying the algorithm and applications of fuzzy clustering is of great significance. This paper introduces the basic knowledge of fuzzy set theory, including the definition of the fuzzy set, its theorem fuzzy relation and so on firstly. Then this paper describes how to use fuzzy clustering analysis method for data classification and the steps of fuzzy clustering analysis.
The Prospect of the Modeling Simulation for the Passive Containment Cooling System of the Advanced PWR in China
Authors: Wang Yan
Published: September 2011

The passive containment cooling system (PCCS) is one main component of the various passive safety systems in the advanced 3rd generation pressurized water reactor. Several containment analysis codes are modified for the simulation and analysis on the PCCS by researchers. These codes for the PCCS were validated by comparison with transient test data from some separate effect tests and integral tests, and used to evaluate the heat-removed capability of the PCCS under the postulated events, such as a loss-of-coolant accident (LOCA) and a main steam line break (MSLB). The advanced 3rd generation pressurized water reactors of AP1000 project were build in China, and the future advanced PWR with higher power will be researched and designed. So it is very important to develop a new code with self-owned intellectual property rights, which is used for the simulation and analysis of the PCCS performance. In this paper, the main ideas of the code design, including the framework of the code, the important mechanism models and the code validation, etc., will be introduced. In addition, the computational fluid Dynamics (CFD) codes also had been applied to solve some thermal-hydraulic problems in Nuclear Reactor Safety (NRS) analysis.
The Second Maintenance and Strengthening of Yonghe Bridge
Authors: Li Hong Jiang
Published: September 2011

Tension rocker bearing (TRB) cables installed at auxiliary piers were critical members to sustain the structural system in a prestressed concrete cable-stayed bridge. Once these cables fractured or broken, its structural system would be transferred. Based on diseases caused by fracture of TRB cables in Yonghe Bridge, corresponding maintenance or strengthening measures were described in detail. These measures included replacement of TRB cables, strengthening of the closure segment of main girder at each side span, and adjustment of stay cable forces. Monitoring results showed that, its structural system was finally and completely rehabilitated, and the safety factor of new TRB cables is enough under the most unfavorable load combination. Moreover, the line shape of main girder and the inclined displacement at the top of each pylon were improved effectively. Thus, Yonghe Bridge accumulated some valuable experience for maintenance or strengthening of existing prestressed concrete cable-stayed bridges, and also made a useful exploration.
Geometrically Nonlinear Stability Study of Self-Anchored Arch-Suspension Bridges
Authors: Qiu Jing , Li Guang Feng , Shen Rui Li
Published: September 2011

The self-anchored arch-suspension bridge is characterized by innovative structure and beautiful shape. In order to research the mechanical characteristics and stability of this structure that has never been built, the proposed preliminary design of the combined system bridge with a main span of 406m is studied. On the basis of the transfer mechanism of live load based on the deflection theories of suspension bridges and arch bridges, the stability of the combined system bridge is analyzed in this paper. The universal finite element software ANSYS is applied to study the linear elastic stability and the geometrically non-linearity stability under six load cases. The study indicates that the transfer mechanism of live load is determined by the distribution of the stiffness. There is no possibility of in-plane instability under live load. The first-order linear elastic instability mode shows the shape of lateral flexure of the junction at mid-span, and the geometrically nonlinear stability is controlled by the lateral flexure. These conclusions can be of some value for the design, calculation and operation management of this structure.
Analysis of Ultimate Load-Bearing Capacity of Long-Span CFST Arch Bridges
Authors: Liu Yang , Wang Da , Zhu Yi Zhou
Published: September 2011

In order to study the ultimate load-bearing capacity of the long-span concrete-filled steel tubular (CFST) arch bridge with fly-bird-type, the ANSYS finite element program was used to establish its special model, and to study ultimate load-bearing capacity of this bridge with three different methods. The constitutive relation factors of concrete-filled steel tubular was taken into consideration including confining effect ultimate load coefficients, failure modes, and load-displacement curves of this bridge under different cases. The result indicate that the ultimate load-bearing capacity of the bridge can meet the requirement, all of its failure modes is out-plane, the two methods, linear elastic buckling analysis and only geometric nonlinearity analysis, will over high estimate ultimate load-bearing capacity of this bridge, and linear elastic buckling method cannot reflect real failure mode of this structure. In order to correctly estimate the ultimate load-bearing capacity of the bridge structure, the effect of geometric and material double nonlinearity couldn’t be neglected.
Review on the Research of Highway Bridges Seismic Damage Assessment
Authors: Yang Sai Ni , Zong Liang , Wang Yuan Qing
Published: September 2011

Highway bridges played an important role in lifeline systems. Their seismic damage status made a direct influence on the implement plan of the earthquake relief work and the life and property security of the people. Therefore, accurate assessment and prediction for the seismic damage of highway bridges were of vital significance, based on which reasonable earthquake fortification could be implemented. This paper summarized and classified the existing seismic damage assessment methods for highway bridges, including certain index evaluation methods based on statistical results, vulnerability index evaluation methods based on probability theory and vulnerability index evaluation methods based on aggregation model. Then the capacity-spectrum method which could be used for calculating the fragility curve and the seismic assessment model of highway bridges used in HAZUS were specially explained. At last, the proposal for the development of seismic assessment systems related with highway bridges in China was put forward. Considering HAZUS’s good performance in seismic assessment, a similar assessment system should be built in China as soon as possible. The first step should be classifying highway bridges in China based on their current situation and obtaining their seismic assessment model parameters roughly, which tend to be safe. The second step should be carrying out sufficient experiments and numerical analysis and revising the model parameters obtained in the first step.
The Natural Bending Vibration of the Continuous Beam and the Impact Factor of Bridge
Authors: Yuan Xiang Rong
Published: September 2011

The natural frequencies and mode shapes of 2, 3 and 4 spans continuous beam with universal cross section are calculated, and these dynamic parameters of 2 spans continuous beam model are measured. From the analysis and the model test, the locations of the maximum curvatures of the mode shapes are determined, and comparing that with the maximum bending moment of the beam under the action of uniformly distributed load, the selection of the natural frequency of the beam is discussed with the General Code for Design of Highway Bridges and Culverts as the impact factors of the beam is calculated. It is shown from the results of the analysis and the test that, for the impact factor, when the effect of positive bending moment caused by impact force is calculated, the fundamental frequency must be used as shown in the General Code, and the 2nd or 3rd frequency must be used when the effect of negative bending moment caused by impact force is calculated. The selection of the frequency should be combined with the mode shape into account for the specific circumstances.
The Apply of Anisotropy Equivalent Flow Model in Research of Tunnel Drainage Influence Radius
Authors: Liu Zhi Chun , Gao Xin Qiang , Sun Ming Lei
Published: September 2011

Tunnel drainage influence range is a difficult hydrological problem. It relates directly to tunnel groundwater environment influence degree in construction and operation stages. Based on Shibanshan tunnel in Shijiazhuang-Taiyuan passenger line, this paper analyses influencing factor of tunnel drainage influence radius and flow transient process adopting heterogeneity and anisotropy equivalent flow models. This paper studies the tunnel drainage influence radius and construction progress , hydrology factors, geological factors and rainfall infiltration factors relations. Research results show that the influence factors are rock permeability, rainfall infiltration recharge and aquifer thickness on tunnel top, less influence factors are structure surface direction, anisotropy characteristic coefficient and primary support of the closed time. The conclusions will provide technical supports for evaluating the tunnel construction of groundwater environmental impact.
Seismic Response Analysis of Horizontal Layer Slope with Soft and Hard Rock Combination
Authors: Feng Wen Kai , Huang Run Qiu , Xu Qiang
Published: September 2011

Slope of subhorizontal layer structure is among typical natural structures and the different soft and hard rock combinations in upper and lower slope parts differ in seismic response. Taking into consideration some slope failure phenomena of two-sided slopes with banded structure ridges in “5.12” Wenchuan Earthquake, simulation experiment are made to research two types of horizontal structure slopes with hard-upper and soft-lower and soft-upper and hard-lower parts, by means of numerical simulation analysis and simulating experiment on vibration table. Research results show that for slope with hard-upper and soft-lower parts, its upper hard rock body is inclined to undergo global shearing deformation, along contact layer with underlying soft rock body, and the upper slope body is apt to go through collapse and pull-crack. For slope with soft -upper and hard -lower parts, influenced relatively more strongly by its lower hard rock part, rock body possibly shows cracking deformation similar to sliding and compression cracking, which may extend upward or downward along the contact layer. Moreover, the shoulder of two-sided slope is apt to undergo pull-crack and that, to some degree, relieves integral stress and sliding deformation of the upper soft rocky body. Therefore the whole rock body goes through little sliding deformation. Research result confirms the actual shatter slope failure, which further verifies the view that horizontal seismic action force plays main role in slope failure.
Study on Sustainable Supply Planning of Water Resources in Ningdong Energy and Chemical Industry Base
Authors: Zhang Ju Ping , Zhang Wei Jiang , Wang De Quan
Published: September 2011

With the expansion of Ningdong Energy and Chemical Industry Base at Lingwu, Ningxia, water shortage is becoming increasingly serious and then has become one of the main factors in restricting the development of society and economy in the region. In the paper, through a systematic analysis of the re-use ways of the sewage as well as the water-saving potential for agricultural purposes, it is suggested that water right trading is the solution when part of the surplus can be used for industrial purposes in the Base, thereby leading to a more reliable way of sustainable water supply and a sustainable and steady economic growth in the region.
Determination and Comparison of Design Ground Motion Parameters in the Small Earthquake Zoning of the Chongqing City
Authors: Wang Gui Zhen , Li Ying Min , Liu Li Ping
Published: September 2011

This paper, based on the Chongqing urban small earthquake zoning, structure of ground calculation model to analysis soil seismic response , determined the design ground motion parameters , and with the current seismic code were compared ,for the general construction projects in Chongqing provides a reference for seismic design . At the same time, it’s of importance to disaster mitigation of other cities, sustainable social and economic development.
Tunnel Supporting Structure Stress and Displacement Characteristics Research
Authors: Chen Sao Qing , Jin Xiao Guang , Jin Yu Juan , Zhu Ling
Published: September 2011

Taking dual carriageway standard cross section given by the current highway tunnel design standard and supporting structure parameters of surrounding rock in V class for example, using ADINA large deformation nonlinear finite element software, this paper divides the supporting structure into small units, and analysis the stress and displacement characteristics in different position of five typical sections in the tunnel construction process. Analysis results show that displacement and stress-time change feature is different apparently between inner and outer side of supporting structure, and also at different sections; displacement at inner and outer side of the same section is similar, while there is considerable difference in different sections; stress at inside and outside of one section is obviously different with that of other sections, which provides scientific basis for the safety of tunnel support structure and the optimized design.
Statistical Analyses of Response Spectra on Medium-Stiff Soil Site
Authors: Liu Wen Feng , Chen Xue Zhong , Sui Jie Ying
Published: September 2011

The analyses on the statistical response spectra have an important role in determining the earthquake demand. Elastic and inelastic spectra on acceleration of the 205 records on medium-stiff soil site for SDOF systems are presented in statistical analyses. The empirical probability distributions of the spectral values are derived according to the Kolmogorov-Smirnov (KS) goodness-of-fit test. The formula for statistical average spectra of the ground motion ensemble are recommended, which are valuable for current research and code revisal. The results show that the statistical averaged elastic α spectra fits well to the design spectra prescribed in Chinese code when the period is smaller than 2s. The inelastic responses decrease with the increase of ductility demand μ when μ<4. The coefficients of variance of the elastic and inelastic spectra are still large and the dispersion cannot be ignored. The probabilistic distribution of the spectra value on acceleration is validated as the lognormal distributions. The proposed formulas give a good fit to the statistical average values.
Failure Mechanisms and Progressive Collapse Judgment Criterion of Space Trusses under Strong Earthquakes
Authors: Wu Hui , Du Wen Feng , Wang Yi Jun
Published: September 2011

Aiming at failure mechanisms and judgment criterion of progressive collapse for space trusses, the responses and the failure mechanisms of diagonal square pyramid space trusses, leaning laid pyramid space trusses and orthogonal square pyramid space trusses with circumferential simple supports under different seismic waves were analyzed in this paper. The results show that space trusses have a good performance of earthquake resistance, but progressive collapse occurs easily. Based on the failure mechanisms of space truss, a judgment criterion of space truss is proposed under strong earthquakes, according to the characteristics of energy, displacements and plastic levels of members. The judgment criterion is expressed by judgment coefficient J. When J>6, space trusses tend to be ductile failure, however, When J> 6, space trusses tend to be progressive collapse.
The Damage in Arch Bridges during 2008 Wenchuan Earthquake
Authors: Huang Yong , Wang Jun Jie , Zheng Xi Yu
Published: September 2011

During the Wenchuan earthquake in 2008, many arch bridges in the seismic zone were damaged. The typical damage included: span collapsed, abutment and arch springing cracked, spandrel arch damaged, damage in the joint member between deck and main arch, damage out of arch plane. Some typical damage examples of the arch bridge are introduced in this paper. The causes and regular pattern features of the earthquake damage are analyzed, and the corresponding countermeasures are proposed.
Seismic Performance Analysis of the Special-Shaped Frame Column Structure on Multi-Dimensional Seismic
Authors: Xu Dong Qiang , He Mei Mei
Published: September 2011

The article considers the two horizontal components of ground motion and torsional component, to do nonlinear time history analysis both on regular and irregular shaped column frame structure models. The results show that torsional component of ground motion haves some impact on torsion reaction of structures, stiffness of irregular shaped column frame structure is uneven, and angle of columns are greater than that of the regular structure; torsion haves some impact on the torque of structure, the torque increases of corner columns is maximum, so corner columns are weak links in shaped column structure, considered fully during the seismic design.
Experimental Heat Transfer for Gas-Liquid Vertical Flow inside Pipe
Authors: Qian Huan Qun , Wang Chang Yong
Published: September 2011

Experiments have been performed to observe flow pattern and investigate convective heat transfer for air-water vertical flow in a forced circulation system. The bubbles motion was recorded by a high-speed CCD camera. For the bubble and slug flow pattern, the temperature fluctuation signals and local heat transfer coefficients were obtained in a short heated tube. The probability density function classical was applied to analyze the temperature. The results qualitatively reflected characteristics of local heat transfer in two phase flow comparing with that in single-phase liquid. The comparison revealed that the gas phase could enhance the heat transfer.
Spatial Analysis of Land Use and Land Cover Changes on the Basis of RS and GIS
Authors: Yu Ming Yang , Meng Fei , Cui Jian
Published: September 2011

The two-period (1990 and 2010) remote sensing images in Longkou City are selected in this article.The temporal and spatial variation of land use in Longkou City is monitored and analyzed by Geo-information Tupu and transfer matrix. Results show that the pattern of the land use change of Longkou City from year 1990 to year 2010 has changed a lot. The relatively stable area accounts for 74.33%, Garden land increases a lot and the increasing area is 14706.53 hm2,accounting for 16.48%. In the past ten years, there is no large-scale land arrangement, so the reason of the change is the economic interests.
Seismic Analysis of a Low Tower Cable-Stayed Bridge and Application of Lead Shear Damper
Authors: Zhou Da Xing , Yan Wei Ming , Chen Yan Jiang , Liu Chang Peng
Published: September 2011

A low tower cable-stayed bridge with a span of 30m+60m+120m+60m+30m had been built before Guidelines for Seismic Design of Highway Bridge was promulgated. Because of its impor¬tance and specificity, it is necessary to do research on seismic performance of this bridge. According to the numerical analysis, it is found that the structural response exceeds the allowance and the bridge might be destroyed if earthquake happened. Here, energy dissipated technology is chosen to cope with this problem. But traditional lead shear damper hasn’t the capabilities of large deformation for some reason and can not be applied to bridge engineering in general case. In this article, a new type of lead shear damper with capabilities of large deformation is used to achieve energy dissipation. Through comparing, it is found that the damping effect of this new damper is as good as that of viscous damper. And the damper has no problem with leakage and metamorphism. What’s more, it is much cheaper than vis¬cous damper. So, lead shear damper has a good prospect in bridge damping.
The Clay Subgrade Compactness Infuences on Life-Span of Asphalt Pavement in Northeast China
Authors: Liu Zhong Gen , Liu Xiao Hong , Yang Zhong Sen , Liang Xiao Feng
Published: September 2011

The life-span of asphalt pavement is influenced by the strength of subgrade , this paper has discussed the modulus of elasticity of subgrade under different compactness . a example of clay subgrade is gived, the pavement structures and traffic data highway are established according to currently asphalt pavement design specification, the pavement bearing abilitie of different subgrade strength is calculated under different compacting conditions, and also a conclusion has been made that a relation between life-span and strength , the calculating results show that the compactness of subgrade cutting down 1% will lead to pavement reducing 0.65 years, through quantitative analysis, it can be believed that improving compaction of subgrade can obviously prolong asphalt pavement life-span.
Study on Influence of Tunnel Excavation on Seismic Performance of Underground Pipeline
Authors: Yang Run Lin , Zhang Tian Yuan
Published: September 2011

It is often necessary to study on the seismic performance of the buried pipelines subjected to tunnel excavation, because the ground motion will inevitably endanger the nearby underground pipelines. In this paper, modeling and analysis of earthquake-resistant performance of tunnel excavation to the upper underground pipeline have been carried out. The changes of stress and displacement of the upper underground pipeline under action of the same seismic wave before and after tunnel excavation was compared. It is showed that there’s a greater impact on the stress and displacement of upper underground pipeline under seismic action, and a tunnel with reasonable supporting would support the underground pipeline to some extent.
The Numerical Simulation Analysis on Safety Stability in Underground Space of Urban Track Transportation System
Authors: Chen Hong Ye , Zhang Jing Fei , Ma Hui Zhong , Ma Jin Ying
Published: September 2011

In order to study and demonstrate the safety condition of urban track transportation system in mechanics area, and to determine the key points and difficulties of this system, it uses FLAC3D numerical simulation software, combines the applied examples of engineering projects, carries on simulation analysis on aspects of surrounding soil’s deformation rule during construction stages, the mechanics analysis during main structure’s construction, and the system surrounding soil’s stress-strain rules during operation stages, etc.. Feasible safety measures and suggestions were proposed accordingly. The applied research indicates that the numerical simulation analysis can express the risk characteristics and rules well during engineering construction and after construction, and further avoid potential hazards or accidents’ occurrence, which has important meanings for ensuring the safety of engineering projects during the whole process.
Stress Analysis of Metro Shield Tunnel Segment — Based on 3D Discontinuous Contact Computational Model
Authors: Li Yu Jie , He Ping , Qin Dong Pin
Published: September 2011

Based on the 1# shield tunnel of SU ZHOU rail transit, a 3D discontinuous contact computational model of shield tunnel segment and bending bolts is built. This paper study about the stress and the deformation of shield tunnel segment with actual loads ,and the influences on shield tunnel segment by properly install the bolts. Result shows that timely apply pre-stress on the bolts could effectively decrease the deformations on segment joint by the shear resistance capacity of the bolts. The maximum deformation reduces from 3.580mm to 0.302mm. And there appear an open-angle which turn to outside or inside on segment joint. The maximum spacing of the open-angle is 0.66mm, and the maximum angle is 0.108 degree. In most position about shield tunnel segment, installed bolts reduced the axial forces and increased or reduced the bending moments.
Study on Settlement of Highway Bed due to Underground Construction of Crossing Railway Tunnels
Authors: Lou Guo Chong , Wang Shu Dong
Published: September 2011

Ground settlement due to construction of underground crossing railway bed is an important issue. In this paper, the influence of the tunnels depths, the elasticity modulus, Poisson’s ratio, and internal friction angle of the sub grade soil property to the ground settlement during construction is simulated by the numerical simulation method. Some conclusions are drawn. Firstly, the tunnels depth doesn’t only influence the growth of the ground settlements, but also the shape of traverse settler. Secondly, the sub grade soil properties mainly affect the larger settlement; the shape of the settlement trough was relatively small.
The Simulation Analysis of Large Cross-Section Soft Rock Tunnel Excavation under the Bias Terrain
Authors: Zhang Gang , Liu Hong Bing
Published: September 2011

Abstract: Taking a High-speed railway tunnel as the background, This paper analyses not only the stress and displacement of surrounding rock , the plastic area distribution and size, but also the size and distribution of initial support internal force in two excavation schemes, based on the criterion of underground engineering structure design theory and rock elastic-plastic succumb Drucker-Prager, Under the guidance of New Austria Tunneling Method, this paper makes numerical simulation of soft rock tunnel excavation in large sections and initial support with the finite software ANSYS11.0. The stress and displacement of surrounding rock and the plastic area distribution and size under two excavation schemes are analyzed, the size and distribution of initial support internal force under two excavation schemes are also investigated .By comprehensive comparing advantages and disadvantages of two schemes, this paper makes some significant conclusions and gives reference for the similar tunnel design and construction.
The Foundation Liquefaction and Permanent Deformation Analysis of Diversion Dike for Nuclear Power Plant
Authors: Zhao Jie , Zheng Yang , Wang Gui Xuan
Published: September 2011

In seismic response analysis, total stress method is adopted mostly, but variation of the pore water pressure and the development process of the liquefaction are not considered in this method. Based on the dynamic analysis of two-dimensional effective stress proposed by Zhu-jiang Shen, combined with dynamic consolidation theory of Biot, the foundation liquefaction analysis of the diversion dike for nuclear power plant is performed by using effective stress dynamic analysis program, the liquefied range is given, as well as the permanent deformation. The obtained law can provide theoretical guidance for the similar project.
Stability Analysis of Tunnel Surrounding Rock Based on Coupled Fluid-Solid Theory
Authors: Wang Fu Ming , Li Xiao Long , Zhong Yan Hui , Chen Xiao Guang
Published: September 2011

Taking Chaijiazhuang Tunnel of Lingnan Expressway as project background, the stability analysis of surrounding rock was performed based on the coupled fluid-solid theory. The distributions of stress field, displacement field and plastic zone of rock mass after excavation of tunnel were discussed considering coupled effect between flow and stress under the condition of different rock level and tunnel depth. Compared with the calculation results of not considering coupling effect, the maximum deformation, maximum principle stress and plastic zone size of wall rock were obviously increased when considering coupling effect, which showed a remarkable influence of coupled fluid-solid effect on the stability of tunnel surrounding rock. Some conclusions were drawn and may provide some guidance to the design and construction of tunnels in water-rich strata.
Numerical Simulation of Lining’s Mechanical Behavior in Subway Tunnel
Authors: Li Li Xin , Li Lei , Li Xin
Published: September 2011

The surface settlement and tunnel lining has a great relationship.To better understand the influence of surface deformation caused by tunnel lining and lining’s stress state,base on Finite Element Method,using ABAQUS Finite Element Analysis Software, analyzed the change of surface displacement and the lining of stress and deformation,respectively,with and without lining.Through the comparison of two cases, the surface settlement and horizontal displacement can be effectivly reduced.The range of influence caused by excavation is greatly narrowed.Because the role of soil,the compressive stress is beared by lining,and the maximum stress is located at both sides of arch waist. These will be referenced for future design and construction.
Numerical Analysis of the Anti-Explosion Effects and Anchored Mechanism of Tunnels Reinforced by Bolts under Top Explosion
Authors: Wang Guang Yong , Guo Jia Qi , Ren Lian Wei
Published: September 2011

The anti-explosion effects and anchored mechanism of tunnels reinforced by bolts were studied by numerical analysis. Comparing with compression-stress curve of the experiments and numerical simulation on the same location of the vault, it indicates that the simulation results are reliable. By contrast the vault displacement of anchored tunnel and unlined tunnel, it can be found that the vault displacement of the tunnel is significantly reduced through the reinforcement with anchor bolts. By comparing the crack distribution of the anchor tunnel and unlined tunnel, it shows that cracks of unlined tunnel are significantly thicker and wider than that of the anchored tunnel, which indicates that the anti-explosion effects of anchor rods are better. It can be known that the anchored bolts supporting can take effect of reinforcement and anti-explosion according to the time-histories curve of the anchor-head.
Prediction of the Toxic and Harmful Gas along the Sichuan-Tibet Railway
Authors: Su Pei Dong
Published: September 2011

The geological setting of Sichuan-Tibet Railway is complicated, while magmatic and metamorphic rocks are widely distributed. Reference to the other engineering experience of underground works under similar geological conditions at home and abroad, the analysis shows that it exists the hazardous possibility that the inorganic gas are toxic and harmful in the tunnels of Sichuan-Tibet Railway. Combining the conditions that inorganic gas produced and the geological conditions along the Sichuan-Tibet Railway, it analyzes and predicates that CH4, CO2, H2S, SO2, CO, NO2, NH3 and H2 are the main types of poisonous gas along the Sichuan-Tibet Railway. The poisonous gas is mainly distributed in the three suture zones, three crustal fault zones and more than three basement fault zones and mafic and ultrabasic rock zone, granites zone, volcanic zone and contact metamorphic zone. All these zones are the favorable migration point to area and gathering area to the toxic and harmful gas. It should be highly mentioned on the construction of the tunnels.
The Effect of Confinement and Defects on Rock Fracture under Dynamic Loads
Authors: Zhou Zhi Rong , Zhu Zhe Ming , Xiao Ding Jun , Jin Xin Xing
Published: September 2011

In order to extract the mineral resources existing at great depths, the mining industry is facing new serious challenges to safe and productive mine operation, and such challenges arise largely as a result of the high pressures imposed on deep mine excavations. In order to investigate the effect of confinement on rock fracturing under dynamic loads, blasting experiments by using cement mortar plates, which are square with a single centralized borehole, have been carried out. Two kinds of confinement, i.e. uniaxial and biaxial, are applied to the square plates. In the study of defect effect, circular cement mortar plates with randomly distributed defects are employed, the results show that confinement and defects affect rock fracturing significantly.
Study on the Structural System of Roof in Fully Mechanized Top Coal Caving
Authors: Shen Jie , Meng Da , Wei Li Ke
Published: September 2011

Based on the structural characters of roof in fully mechanized top coal caving, mechanical analysis, mechanical calculation and simulation experiment were used to explore the particularity of roof structure in fully mechanized top coal caving. The simplified model of roof structure was built in final. The results shown that, during the mining by fully mechanized top coal caving, dynamic balance arch structure was formed by the roof and surrounding rock in working face. In the same time, multi span beam structure was formed in the tendency direction. The results of this paper would provide the theory basis for exploring the strata behavior regularity in further, and promote the safety in production of coal mining enterprises.