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Numerical Integration with Derivatives

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Journal of southwest jiaotong university(English Edition) 2006年第2期14卷 200-204页

作者：胡成 Department of Mathematics Southwest Jiaotong University Chengdu 610031China

A new formula with derivatives for numerical integration was presented. Based on this formula and the Richardson extrapolafion process, a numerical integration method was established. It can converge faster than the Romberg＇s. With the same accuracy, the computation of the new numerical integration with derivatives is only half of that of Romberg＇s numerical integration.

关键词： Derivafives Richardson extrapolation process Romberg integration method

Coupled Vibration of Long-Span Railway Curved Girder Bridges and Vehicles

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Journal of southwest jiaotong university(English Edition) 2005年第1期13卷 62-69页

作者：单德山李乔 Department of Bridge and Structural engineering Southwest Jiaotong University Chengdu 610031 China

The structure of a long curved girder bridge is represented with a three-dimensional curved finite element model. Each 4-axle ~vehicle is modeled by a dynamic system of 35 degrees of freedom. The random irregularities of the track are generated from a power spectral density function under the given track condition. The dynamic interaction between the bridge and train is realized through the contact forces between the wheels and track. Then based on these models, the coupled equations of motion are solved by applying the time-integration and iteration techniques to the coupled system. The proposed formulation and the associated computer program are then applied to a real curved girder bridge. The dynamic responses of the bridge-vehicle system and the derailments and offload factors related to the riding and running safeties of vehicles are computed. The results show that the formulation presented in this paper can well predict dynamic behaviors of both bridge and train with reasonable computation efforts.

关键词： Corpled Vibration Curved girder bridge Vehicle

Effects of Lateral Motion on the Creep Forces in Wheel/Rail Rolling Contact

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Journal of Modern Transportation 1997年第1期14卷 45-55页

作者： Jin Xuesong Zhang Weihua Hu Liujia National Traction Power Laboratory, southwest jiaotong university, chengdu 610031, china

The influences of the lateral motion of a single wheelset running on a tangent railway on the creepages and creep forces between wheel and rail are investigated with numerical methods. The effect of the yaw motion of wheelset is neglected in the analysis, and Kalker’s theory of three dimensional elastic bodies in rolling contact is employed to analyze the creep forces in the wheel/rail rolling contact with Non Hertzian form.

关键词： lateral motion wheel/rail rolling contact creepage creep force

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高烈度地震区隧道设置减震层的减震原理研究

土木工程学报 2011年第8期44卷 126-131页

作者：王明年崔光耀西南交通大学四川成都610031

现场调查表明:汶川大地震震区隧道结构受到比较严重的破坏,严重影响了灾区救援和重建,可见传统的隧道抗震技术已不能保证高烈度地震区隧道结构的安全,为此利用波动理论对隧道减震层减震模型进行研究,推导地震波沿隧道结构轴线方向作用... 详细信息

现场调查表明:汶川大地震震区隧道结构受到比较严重的破坏,严重影响了灾区救援和重建,可见传统的隧道抗震技术已不能保证高烈度地震区隧道结构的安全,为此利用波动理论对隧道减震层减震模型进行研究,推导地震波沿隧道结构轴线方向作用下的减震计算公式,研究减震层厚度、减震层弹性模量、减震层刚度和地震波输入频率等参数对隧道减震效果的影响,并通过室内模型试验验证隧道减震层减震模型的减震效果。研究成果可为高烈度地震区隧道结构减震设计提供参考。

关键词：高烈度地震区减震层减震原理减震模型试验

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南京地铁盾构掘进施工的三维有限元仿真分析

铁道学报 2005年第1期27卷 84-89页

作者：张志强何川佘才高西南交通大学土木工程学院四川成都610031 南京地铁有限责任公司江苏南京210024

论文依托南京地铁区间盾构隧道工程,建立了模拟盾构机(包括刚度、自重、推力)前行掘进隧道的三维有限元力学模型,在此基础上,研究了随盾构顶进引起的地表沉隆变形以及隧道围岩、管片变形,研究结果为南京地铁区间盾构隧道工程的施工及监... 详细信息

论文依托南京地铁区间盾构隧道工程,建立了模拟盾构机(包括刚度、自重、推力)前行掘进隧道的三维有限元力学模型,在此基础上,研究了随盾构顶进引起的地表沉隆变形以及隧道围岩、管片变形,研究结果为南京地铁区间盾构隧道工程的施工及监控量测提供了参考。

关键词：盾构隧道施工盾构机前行三维有限元沉隆变形分析

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小波分析在机车优化粘着控制中的应用

铁道学报 2003年第5期25卷 32-38页

作者：王辉肖建西南交通大学电气工程学院四川成都610031

分析了机车粘着控制中粘着利用机理,提出了空转趋势识别方法,并采用小波变换这一工具对含有随机干扰信号的瞬时轮周加速度信号进行了多分辨率分析,即把轮周加速度信号分解为多个层次的细节部分和平滑部分。轮周加速度信号中的噪声被分... 详细信息

分析了机车粘着控制中粘着利用机理,提出了空转趋势识别方法,并采用小波变换这一工具对含有随机干扰信号的瞬时轮周加速度信号进行了多分辨率分析,即把轮周加速度信号分解为多个层次的细节部分和平滑部分。轮周加速度信号中的噪声被分解到了各层的细节部分,由剩余的平滑部构成轮周加速度发展趋势曲线,并对其微分。然后根据其加速度微分值进行空转趋势识别。最后,给出了仿真结果表明:基于空转趋势识别方法的模糊粘着控制能充分利用粘着力,避免空转发生;小波分析方法的应用有效避免空转趋势误识别,提高了粘着控制稳定性。

关键词：空转趋势识别小波变换多分辨率分析粘着控制

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简支梁桥有载频率分析

西南交通大学学报 2004年第5期39卷 628-632页

作者：唐贺强沈锐利西南交通大学土木工程学院四川成都610031

根据桥梁固有频率的定义求解桥梁振动微分方程,给出了列车荷载作用下简支梁桥有载频率的解析表达式.研究表明,桥梁有载频率与其上作用车辆的简化模型、过桥车辆数、行车速度以及桥梁跨度等有关:1辆车简化为4个或2个轮对时,桥梁有载频率... 详细信息

根据桥梁固有频率的定义求解桥梁振动微分方程,给出了列车荷载作用下简支梁桥有载频率的解析表达式.研究表明,桥梁有载频率与其上作用车辆的简化模型、过桥车辆数、行车速度以及桥梁跨度等有关:1辆车简化为4个或2个轮对时,桥梁有载频率很接近,比较符合实际情况;车辆总长超过桥梁跨度时,桥梁有载频率呈稳定的周期性变化;桥梁有载频率随时间变化,与车辆在桥上的位置有关,且行车速度越快,频率变化越快.

关键词：简支梁车桥耦合微分方程固有频率

A New Aggregation Operator Based on Mapping and Its Evaluation Application

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A New Aggregation Operator Based on Mapping and Its Evaluati...

Theoretical　and　Experimental　Study　of　Hopf　Bifurcation　and　Limit　Cycles　of　Railway　Vehicle　Hunting

2008 3rd International Conference on Intelligent System and Knowledge engineering(ISKE 2008)

作者： Xiaoping Qiu Xiaobing Li Kaijun Xu Hongwei Ma School of Logistics southwest jiaotong university chengdu Sichuan 610031 .china Department of Mathematics southwest jiaotong university chengdu Sichuan 610031 china

A new aggregation operator is proposed in this paper,which is defined based on mapping,whose input and output variables can be assigned by several different types of score terms,such as numbers,intervals,linguistic values or symbolic ***,the definition of the aggregation operator is introduced,followed by the definitions of the layered relationship among the evaluation items with the aggregation operators in order to establish an evaluation system,in which the database technology is involved for better ***,the three main algorithms in the evaluation process are described in ***,the experiment with the logistics-effectiveness evaluation is carried out for validating the effective of the aggregation operator.

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Journal of Modern Transportation 1996年第2期13卷 21-28页

作者： Zeng Jing Zhang Weihua Shen Zhiyun National Traction Power Laboratory,southwest jiaotong university,chengdu 610031,china National Traction Power Laboratory Southwest Jiaotong University Chengdu 610031 China

The nonlinear hunting stability of railway vehicles is studied theoretically and experimentally in this *** Hopf bifurcation point is determined through c... 详细信息

The nonlinear hunting stability of railway vehicles is studied theoretically and experimentally in this *** Hopf bifurcation point is determined through calculating the eigenvalues of the system linearization equations incorporating with the golden cut *** bifurcated limit cycles are computed by use of the shooting method to solve the boundary value problem of the system differential *** validation to the numerical results is carricd out by utilizing the full scale roller test rig.

关键词： railway vehicle stability Hopf bifurcation limit cycle roller rig