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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

Further research on high-spin structure in ^(161)Lu

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Science china(Physics,mechanics & Astronomy) 2008年第3期51卷 315-320页

作者： LI YanXia1,2,YU ShaoYing1,2,4,SHEN CaiWan1,5,LI XiaoWei6 & CHEN YongShou3,4 1 school of Science,Huzhou Teachers College,Huzhou 313000,china 2 College of Mathematics,Physics and Information engineering,Zhejiang Normal university,Jinhua 321000,china 3 china Institute of Atomic Energy,Beijing 102413,china 4 Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100080,china 5 Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of lanzhou,lanzhou 730000,china 6 Department of Physics,Chifeng university,Chifeng 024001,china school of Science Huzhou Teachers College Huzhou 313000 China College of Mathematics Physics Information engineering Zhejiang Normal University Jinhua 321000 China china Institute of Atomic Energy Beijing 102413 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China Department of Physics Chifeng University Chifeng 024001 China

The two-dimensional total routhian surface (TRS) calculations were performed to probe into the triaxial superdeformed characteristics of a strongly populated band X2 in 161Lu. This band was identified as a triaxial superdeformed band by using our TRS method. We also got its formation mechanics,i.e. the neutron-shell correction energy plays a crucial role,while the rotating energy and the deformation-driving effect of high j intruder orbit i13/2 also play an additional role.

关键词： TRS method triaxial superdeformation formation mechanism

Factors Affecting the Relation of Fracture Toughness V_(GC) with Critical Void Growth Ratio R_C/R_O

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Journal of Materials Science & Technology 1998年第6期14卷 574-576页

作者： Li ZHOU(Department of civil engineering, Wuyi university,Jiangmen 529020, china) Department of civil engineering Wuyi University Jiangmen 529020 China

The relationship between fracture toughness VGC and critical void growth RC/RO was studied for ten kinds of Steel. The macroscopic fracture toughness VGC was determined by using notched tensile specimens. and the microscopic parameters of critical void growth ratio RC/RO were quantitatively measured under SEM. Then, the coefhcient C in the relation VGC = C In(RC/RO) proposed in author's past work was specifically explored. The correlation of C with tensile proderty parameter φ=σyδ/(Eφn) was presented for the Steel investigated, and the effects of low temperature on C were also discussed. Results show that the coefficient C is linearly related to the parameter and insensitive to low temperature.

关键词： GC with Critical Void Growth Ratio R_C/R_O Factors Affecting the Relation of Fracture Toughness V

Unified solutions for stresses and displacements around circular tunnels using the Unified Strength Theory

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Science china(Technological Sciences) 2010年第6期53卷 1694-1699页

作者： ZHANG ChangGuang1,WANG JiangFeng2 & ZHAO JunHai3 1 Department of Geotechnical engineering,Tongji university,Shanghai 200092,china 2 North china Institute of Water Conservancy and Hydroelectric Power,Zhengzhou 450011,china 3 school of civil engineering,Chang’an university,Xi’an 710061,china 1. Department of Geotechnical engineering Tongji University Shanghai 200092 China2. North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450011 China3. School of Civil Engineering Chang’an University Xi’an 710061 China

The unified solutions are presented for stresses and displacements around a circular tunnel subjected to a hydrostatic stress *** rock mass is assumed to be elastic-brittle-plastic and governed by the Unified Strength *** displacements are obtained accounting for three different definitions for elastic strains and different Young's modulus in the plastic *** unified solutions obtained in this paper are especially versatile in reflecting the intermediate principal stress effect to different extents for different *** conventional solutions,based on the Mohr-Coulomb failure criterion and the Generalized Twin Shear Stress yield criterion,are special cases of the present unified *** new unified solutions can compare with those computed by the latest generalized Hoek-Brown failure *** results obtained demonstrate the importance of the intermediate principal stress influence for the stresses and displacements *** effects of different definitions for elastic strains and different Young's modulus in the plastic zone on the displacements are significant.

关键词： Unified Strength Theory intermediate principal stress different definitions for elastic strains different Young’s modulus

One-dimensional nonlinear consolidation of soft clay with the non-Darcian flow

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Journal of Zhejiang university-Science A(Applied Physics & engineering) 2013年第6期14卷 435-446页

作者： Chuan-xun LI Kang-he XIE Faculty of civil engineering and mechanics Jiangsu University Research Center of Coastal and Urban Geotechnical engineering Zhejiang University

Based on the non-Darcian flow law described by exponent m and threshold gradient i 1 under a low hydraulic gradient and the classical nonlinear relationships e-lgσ′ and e-lgk v (Mesri and Rokhsar, 1974), the governing equation of 1D nonlinear consolidation was modified by considering both uniform distribution of self-weight stress and linear increment of self-weight stress. The numerical solutions for the governing equation were derived by the finite difference method (FDM). Moreover, the solutions were verified by comparing the numerical results with those by analytical method under a specific case. Finally, consolidation behavior under different parameters was investigated, and the results show that the rate of 1D nonlinear consolidation will slow down when the non-Darcian flow law is considered. The consolidation rate with linear increment of self-weight stress is faster than that with uniform distribution one. Compared to Darcy's flow law, the influence of parameters describing non-linearity of soft soil on consolidation behavior with non-Darcian flow has no significant change.

关键词： Non-Darcian flow Nonlinear consolidation Time-dependent loading Uniform distribution of self-weight stress Linear increment of self-weight stress

Research progress of the NSFC Major Research Plan “Dynamic Disaster Evolution of Major engineering Structures”

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Science china(Technological Sciences) 2010年第2期53卷 592-594页

作者： RU JiPing1, LI DaPeng1, LI ZhongXian2 1 Department of engineering & Materials Science, NSFC, Beijing 100085, china 2 school of civil engineering, Tianjin university, Tianjin 300072, china 1. Department of engineering & Materials Science NSFC Beijing 100085 China2. School of Civil Engineering Tianjin University Tianjin 300072 China

The NSFC Major Research Plan aims to conduct researches at the international research frontiers on modeling of strong earthquake ground motions and strong wind or typhoon fields, and investigating the damage and failure evolution process of the major engineering structures under dynamic actions, focusing on the following two key scientific problems: (1) characteristics and laws of strong earthquake ground motions and strong wind or typhoon fields, and (2) process and mechanism of dynamic disaster evolution of the major engineering structures. For these goals, the research work is targeted at (1) modeling and predicting of strong earthquake ground motion and strong wind or typhoon fields, (2) identifying critical parameters influencing the dynamic disaster evolution of the major engineering structures, (3) analyzing the whole dynamic disaster evolution process of the major engineering structures, and (4) integration and verification of simulation systems for dynamic disaster evolution of the major engineering structures.

关键词： major engineering structures dynamic disaster evolution research progress

Experimental study on bed-load sediment transport under irregular wave and current combined flow

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Acta Oceanologica Sinica 2001年第2期20卷 271-280页

作者： Wu Yongsheng,Qin Chongren (1. Department of Hydraulic engineering, Tsinghua university, Beijing 100084, china 2. school of civil engineering, Tianjin university, Tianjin 300072, china) Department of Hydraulic engineering Tsinghua University Beijing 100084 China

Using an irregularly oscillating tray and flume, a series of experiments are completed to evaluate bed-load sediment transport rate under irregular wave -current coexistent field. Testing conditions include three interaction angles 0', 45', 90' and two kinds of median sizes (0.38 and 1.10 mm). The results of transport rate show that the net sediment transport rate can be expressed approximately as the function of the maximum bottom shear stress of waves, mean shear stress of current and the grain size.

关键词： Irregular wave-current bed-load transport rate

An adaptive scaled boundary finite element method by subdividing subdomains for elastodynamic problems

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Science china(Technological Sciences) 2011年第S1期54卷 101-110页

作者： ZHANG ZiHua 1,2,YANG ZhenJun 2,LIU GuoHua 1 & HU YunJin 1 1 College of civil engineering and Architecture,Zhejiang university,Hangzhou 310058,china 2 school of engineering,university of Liverpool,L69 3GQ,UK 1. College of civil engineering and Architecture Zhejiang University Hangzhou 310058 China 2. school of engineering University of Liverpool Liverpool L69 3GQ UK

The scaled boundary finite element method(SBFEM) is a semi-analytical numerical method,which models an analysis domain by a small number of large-sized subdomains and discretises subdomain boundaries *** a subdomain,all fields of state variables including displacement,stress,velocity and acceleration are semi-analytical,and the kinetic energy,strain energy and energy error are all integrated *** advantages are taken in this study to develop a posteriori h-hierarchical adaptive SBFEM for transient elastodynamic problems using a mesh refinement procedure which subdivides *** only a small number of subdomains are subdivided,mesh refinement is very simple and efficient,and mesh mapping to transfer state variables from an old mesh to a new one is also very simple but *** 2D examples with stress wave propagation were *** results show that the developed method is capable of capturing propagation of steep stress regions and calculating accurate dynamic responses,using only a fraction of degrees of freedom required by adaptive finite element method.

关键词： scaled boundary finite element method subdivision of subdomains h-hierarchical adaptivity mesh mapping transient elastodynamics

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牵引变压器绕组变形在线检测方法研究

铁道学报 2004年第2期26卷 60-65页

作者：高仕斌王果西南交通大学电气工程学院四川成都610031

国内外的研究和统计表明,变压器绕组变形是电力系统安全运行的一大隐患,通过测量变压器绕组短路电抗来判断变压器绕组是否变形是一种有效的方法。本文提出了2种通过在线监测原、次边的电压和电流,实时计算绕组的短路电抗来判断变压器绕... 详细信息

国内外的研究和统计表明,变压器绕组变形是电力系统安全运行的一大隐患,通过测量变压器绕组短路电抗来判断变压器绕组是否变形是一种有效的方法。本文提出了2种通过在线监测原、次边的电压和电流,实时计算绕组的短路电抗来判断变压器绕组变形的方法,并对电气化铁路主要接线形式的牵引变压器绕组变形的在线监测方案进行了设计。论文分析了互感器误差对短路电抗测量结果的影响;通过变压器建模,分析了磁滞特性和负载变化大小对短路电抗测量结果的影响,验证了该方法在工程应用上的可行性。

关键词：变压器绕组变形短路电抗在线监测