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Analysis theory of random energy of train derailment in wind

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 751-757页

作者： CHEN RuiLin 1,2,3 , ZENG QingYuan 3 , HUANG YunQing 1 , XIANG Jun 3 , WEN Ying 3 , GUO XiaoGang 2 , YIN ChangJun 2 , DONG Hui 2 & ZHAO Gang 4 1 Hunan Key Laboratory for Computation and Simulation in Science and engineering, Xiangtan University, Xiangtan 411105, china 2 school of civil engineering & Mechanics, Xiangtan University, Xiangtan 411105, china 3 school of civil Architecture, Central South University, Changsha 410075, china 4 AMEC, Toronto M5A5G7, Canada 1. Hunan Key Laboratory for Computation and Simulation in Science and engineering Xiangtan University Xiangtan 411105 China2. School of Civil Engineering & Mechanics Xiangtan University Xiangtan 411105 China3. School of Civil Architecture Central South University Changsha 410075 China4. AMEC Toronto M5A5G7 Canada

Based on the analysis theory of random energy of train derailment, an analysis theory of random energy of train derailment in wind is suggested. Two methods are proposed -the time domain method and the frequency domain method of analysis theory of random energy of train derailment in wind. The curves of σ pw -v under various wind speeds are obtained through the computation. The original curve of σ p -v is expanded, which turns the analysis theory of random energy of train derailment into the all-weather theory. Train derailment condition has been established under wind action. The first and second criterions of train derailment have been proposed in light of wind action. The analysis of train derailment cases at home or abroad is made, in- cluding the first analysis of Xinjiang train derailment case encountered 13-level of gale, which explained the inevitability of train derailment. The analysis theory of random energy of train derailment in wind shows its validity and accuracy. The input energy σ pw of the transverse vibration of train-track(bridge)-wind system is linked to train speed. With the establishment of the analysis theory of random energy of train derailment in wind, It is likely to initiate an all-weather speed limit map for a train or any high-speed train.

关键词： train derailment analysis theory of random energy of train derailment analysis theory of random energy of train de- railment in wind train derailment condition in wind the criterion of train derailment in wind train derailment case

An approach to 3D NURBS modeling of complex fault network considering its historic tectonics

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Progress in Natural Science:Materials International 2006年第5期16卷 546-553页

作者： ZHONG Denghua, LIU Jie and LI Mingchao (school of civil engineering, Tianjin University, Tianjin 300072, china) school of civil engineering Tianjin University Tianjin 300072 China

Fault disposal is a research area that presents difficulties in 3D geological modeling and visualization. In this paper, we propose an integrated approach to reconstructing a complex fault network (CFN). Based on the non-uniform rational B-spline (NURBS) techniques, fault surface was constructed, reflecting the regulation of its spatial tendency, and correlative surfaces were enclosed to form a fault body model. Based on these models and considering their historic tectonics, a method was put forward to settle the 3D modeling problem when the intersection of two faults in CFN induced the change of their relative positions. First, according to the relationships of intersection obtained from geological interpretation, we introduced the topological sort to determine the order of fault body construction and rebuilt fault bodies in terms of the order; then, with the disposal method of two intersectant faults in 3D modeling and applying the Boolean operation, we investigated the characteristic of faults at the intersectant part. An example of its application in hydropower engineering project was proposed. Its results show that this modeling approach can increase the computing efficiency while less computer memory is required, and it can also factually and objectively reproduce the CFN in the engineering region, which establishes a theoretical basis for 3D modeling and analysis of complex engineering geology.

关键词： fault network NURBS technique historic tectonics topological sort 3D modeling.

An effective and practical method for solving an unnegligible problem inherent in the current calculation model for multi-support seismic analysis of structures

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Science china(Technological Sciences) 2010年第7期53卷 1774-1784页

作者： LIU GuoHuan2, GUO Wei1 & LI HongNan2 1 National engineering Laboratory for High Speed Railway Construction, school of civil engineering and Architecture, Central South University, Changsha 410075, china 2 Faculty of Infrastructure engineering, Dalian University of Technology, Dalian 116024, china 2. Faculty of Infrastructure engineering Dalian University of Technology Dalian 116024 China1. National Engineering Laboratory for High Speed Railway Construction School of Civil Engineering and Architecture Central South University Changsha 410075 China

In the seismic analysis of extended structures subject to spatially varying motions, the displacement input model instead of acceleration model is usually adopted for accurate results. In this paper, a more detailed and comprehensive analysis of the displacement input model is carried out and the research shows that there exists an unnegligible problem in the current displacement model, which leads to the irrationality and unconvergence of some calculated results such as base shear etc. Based on the situation, an effective method named massless rigid element (MRE) method is presented to solve the problem. Moreover, the rationality and accuracy of the method are further assessed and the method is applied to a transmission tower-line system project using the commercially available structural analysis software SAP2000. The theoretical and numerical analyses indicate that the MRE approach is not only feasible with sufficient computational accuracy but also practical and can be easily implemented using the commercially available finite element software such as SAP2000.

关键词： extended structures seismic responses spatially varying motions displacement input model massless rigid element (MRE) transmission tower-line system

Preliminary study on interaction between plant frictional root and rock-soil mass

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Science china(Technological Sciences) 2010年第7期53卷 1938-1942页

作者： YAN ZhiXin1’2, SONG Yun3, JIANG Ping1’2 & WANG HouYu4 1 Key Laboratory of Mechanics on Disaster and Environment in Western china (Lanzhou University), Ministry of Education, Lanzhou 730000, china 2 school of civil engineering and Mechanics, Lanzhou University, Lanzhou 730000, china 3 College of civil engineering and Mechanics, Central South University of Forestry and Technology, Changsha 410004, china 4 Air Force engineering Design & Research Bureau, Beijing 100077, china 1. Key Laboratory of Mechanics on Disaster and Environment in Western china (Lanzhou University) Ministry of Education Lanzhou 730000 China2. School of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China3. College of Civil Engineering and Mechanics Central South University of Forestry and Technology Changsha 410004 China4. Air Force Engineering Design & Research Bureau Beijing 100077 China

The interaction between lateral root system of woody plant and soil mass is similar to the one between shrub, herbage and soil mass, and has the effect of frictional reinforcement on slope soil. It plays an important role in reinforcing soil strength in shallow slope. Therefore, slope soil mass can be considered as a composite of soil and plant roots and the soil strength and stability of shallow slope soil mass are improved. However, current researches still remain on the level of qualitatively analyzing the relation between root and soil mass. In this paper, some exploratory researches on quantitative analysis of the interaction mechanism between root and soil mass are conducted. With the study of interaction between herbage root system (lateral root system of woody plants) and soil mass, the mechanical model of interaction between frictional root and soil mass is established. The accuracy of the model is verified by field experiments of Pinus Yunnanensis. The mechanical model provides a crucial theoretical guidance to quantitatively analyzing the interaction between plant root and soil mass; it also has certain values in application.

关键词： plant slope protection vegetation for slope protection mechanical model frictional root

3D thermo-hydro-mechanical-migratory coupling model and FEM analyses for dual-porosity medium

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Science china(Technological Sciences) 2010年第8期53卷 2172-2182页

作者： ZHANG YuJun 1&ZHANG WeiQing 2 1 State Key Laboratory of Geomechanics and Geotechnical engineering,Institute of Rock and Soil Mechanics, Chinese Academy of Sciences,Wuhan 430071,china 2school of civil engineering,Southwest Jiaotong University,Chengdu 610031,china 1. State Key Laboratory of Geomechanics and Geotechnical engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China2. School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China

One kind of 3D coupled thermo-hydro-mechanical-migratory model for saturated-unsaturated dual-porosity medium was established,in which the stress field and the temperature field are single,but the seepage field and the concentration field are double,and the influences of sets,spaces,angles,continuity ratios,stiffness of fractures on the constitutive relationship of the medium can be *** relative three-dimensional program of finite element method was also *** comparing with the existing computation example,reliability of the model and the program were *** a hypothetical nuclear waste repository as a calculation example,the radioactive nuclide leak was simulated numerically with both the rock mass and the buffer being unsaturated media,and the temperatures,negative pore pressures,flow velocities,nuclide concentrations and normal stresses in the rock mass were *** results showed that the temperatures,negative pore pressures and nuclide concentrations in the buffer all present nonlinear changes and distributions that even though the saturation degree in porosity is only about 1/9 of that in fracture,the flow velocity of underground water in fracture is about 6 times of that in porosity because the permeability coefficient of fracture is almost four orders higher than that of porosity,and that the regions of stress concentration occur at the vicinity of two sides of the boundary between buffer and disposal pit wall.

关键词： dual-porosity medium thermo-hydro-mechanical-migratory coupling three-dimensional model FEM analysis

Nonlinear analysis of slow drift extreme responses of a compliant offshore structure

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Acta Mechanica Sinica 2009年第5期25卷 651-657页

作者： Yingguang Wang Jiahua Tan school of Naval Architecture, Ocean and civil engineering,Shanghai Jiao Tong University, 200240 Shanghai, china school of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University 200240 Shanghai China

This paper first demonstrates that the accuracy and efficiency of the method of numerical simulation often used is not very high in predicting the slow drift surge extreme responses of a compliant offshore structure. Next, the slow drift surge extreme responses of the structure are analyzed via the path integral solution racy and efficiency of the PIS （PIS） method, and the accumethod is found to be higher than those of the numerical simulation method. A compound PIS （CPIS） method is first proposed in this article to further improve the efficiency of the path integral solution method, and the accuracy and efficiency of the CPIS method is validated.

关键词： Compliant offshore simulation Path integral solution solution structure Numerical Compound path integral

Study on multi-scheme analysis and evaluation method for concrete sequence placement of high arch dam

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Science china(Technological Sciences) 2011年第S1期54卷 47-53页

作者： ZHONG GuiLiang,REN BingYu & TONG DaWei Department of Hydraulic and Hydroelectric engineering,school of civil engineering,Tianjin University,Tianjin 300072,china 1. Department of Hydraulic and Hydroelectric engineering School of Civil Engineering Tianjin University Tianjin 300072 China

A complete scheme for solving the key scientific problems of how to make concrete sequence placement scheme of high arch dam reasonable and feasible and how to meet the need of construction process was ***,based on a coupling analysis of concrete sequence placement system of high arch dam,a mathematical model considering complex construction constraints was ***,a multi-scheme computational analysis method for concrete sequence placement of high arch dam was proposed based on dynamic ***,a multi-scheme evaluation method for concrete sequence placement was put forward based on analytic hierarchy ***,feedback guidance for progress control and management in the high arch dam construction process was ***,these methods were applied to a practical project to show that the methods can analyze and evaluate multi-scheme for concrete sequence placement of high arch dam effectively,optimize the process of dam concrete sequence placement,and recommend engineering *** methods provide new theoretical principles and technical measures for real-time progress control in the high arch dam construction.

关键词： sequence placement analysis multi-scheme evaluation dynamic simulation analytic hierarchy process high arch dam construction

LINEAR ACTIVE STRUCTURES AND MODES (Ⅰ) —BASIC CONCEPTS AND PROPERTIES

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Applied Mathematics and Mechanics(English Edition) 2004年第8期25卷 845-853页

作者：张景绘龚靖school of civil engineering and Mechanics Xi'an Jiaotong University Xi'an 710049 P.R.china Department of civil engineering Northeast china Institute of Electric Power Jilin 132012 P.R.china 王永刚school of civil engineering and Mechanics Xi'an Jiaotong University Xi'an 710049 P.R.china school of Science Chang'an University Xi'an 710064 P.R.china school of civil engineering and Mechanics Xi'an Jiaotong University Xi'an 710049 P.R.China

Some basic concepts about the active structures were firstly explained, and the main subjects to study in the field of active structure dynamics were synthesized. For the linear active structures, the annotations on the modes were done in detail. The physical meanings of the right and left eigenvectors were explained. The right eigenvectors are the modal shapes and the modal responses of an active structure depend on the left ones. The adjoint structure of an active structure was defined and the reciprocity theorem was interpreted. For two active structures, which are adjoint to each other and with the reciprocal gain-matrices, the right and left eigenvector are reciprocal. The relationship between an active structure and the corresponding passive structure is expressed with the transfer functions, which is employed to resolve the estimation problems.

关键词： active structure vibration control smart structure mode

Research on analysis method for temperature control information of high arch dam construction

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Science china(Technological Sciences) 2011年第S1期54卷 40-46页

作者： ZHONG DengHua,ZHAO ChenSheng & REN BingYu Department of Hydraulic and Hydroelectric engineering,school of civil engineering,Tianjin University,Tianjin 300072,china 1. Department of Hydraulic and Hydroelectric engineering School of Civil Engineering Tianjin University Tianjin 300072 China

Temperature control,which is directly responsible for the project quality and progress,plays an important role in high arch dam *** to discover the rules from a large amount of temperature control information collected in order to guide the adjustment of temperature control measures to prevent cracks on site is the key scientific *** this paper,a mathematic logical model was built firstly by means of a coupling analysis of temperature control system decomposition and coordination for high arch ***,an analysis method for temperature control information was presented based on data mining ***,the data warehouse of temperature control was designed,and the artificial neural network forecasting model for the highest temperature of concrete was also ***,these methods were applied to a practical project. The result showed that the efficiency and precision of temperature control was improved,and rationality and scientificity of management and decision-making were *** of these researches provided an advanced analysis method for temperature control in the high arch dam construction process.

关键词： high arch dam construction temperature control information data mining data warehouse neural network model