Bridges crossing active faults are more likely to suffer serious damage or even collapse due to the wreck capabilities of near-fault pulses and surface ruptures under earthquakes.Taking a high-speed railway simply-sup...Bridges crossing active faults are more likely to suffer serious damage or even collapse due to the wreck capabilities of near-fault pulses and surface ruptures under earthquakes.Taking a high-speed railway simply-supported girder bridge with eight spans crossing an active strike-slip fault as the research object,a refined coupling dynamic model of the high-speed train-CRTS III slab ballastless track-bridge system was established based on ABAQUS.The rationality of the established model was thoroughly discussed.The horizontal ground motions in a fault rupture zone were simulated and transient dynamic analyses of the high-speed train-track-bridge coupling system under 3-dimensional seismic excitations were subsequently performed.The safe running speed limits of a high-speed train under different earthquake levels(frequent occurrence,design and rare occurrence)were assessed based on wheel-rail dynamic(lateral wheel-rail force,derailment coefficient and wheel-load reduction rate)and rail deformation(rail dislocation,parallel turning angle and turning angle)indicators.Parameter optimization was then investigated in terms of the rail fastener stiffness and isolation layer friction coefficient.Results of the wheel-rail dynamic indicators demonstrate the safe running speed limits for the high-speed train to be approximately 200 km/h and 80 km/h under frequent and design earthquakes,while the train is unable to run safely under rare earthquakes.In addition,the rail deformations under frequent,design and rare earthquakes meet the safe running requirements of the high-speed train for the speeds of 250,100 and 50 km/h,respectively.The speed limits determined for the wheel-rail dynamic indicators are lower due to the complex coupling effect of the train-track-bridge system under track irregularity.The running safety of the train was improved by increasing the fastener stiffness and isolation layer friction coefficient.At the rail fastener lateral stiffness of 60 kN/mm and isolation layer friction coefficients of 0.9 and 0.8,r展开更多
使用32位微控制器MPC5604开发了车辆电子稳定性控制系统的电子控制单元(Electronic Control Unit,ECU)。建立了七自由度车辆模型,并制定了基于横摆角速度门限值的控制策略;选择双移线工况作为仿真工况,运用Matlab/Simulink软件实现离线...使用32位微控制器MPC5604开发了车辆电子稳定性控制系统的电子控制单元(Electronic Control Unit,ECU)。建立了七自由度车辆模型,并制定了基于横摆角速度门限值的控制策略;选择双移线工况作为仿真工况,运用Matlab/Simulink软件实现离线仿真分析,同时通过台架试验,对比了32位控制器及16位控制器的系统运行代码时间。离线仿真结果及台架反馈的信息表明,所建立的车辆稳定性控制系统能够较好地提升极限工况下汽车的操纵稳定性,同时32位微控制器能使系统整体性能得到提升,为更加复杂的算法应用提供了扩展的空间。展开更多
基金Project(51378050) supported by the National Natural Science Foundation of ChinaProject(B13002) supported by the “111” Project,China+2 种基金Project (8192035) supported by the Beijing Municipal Natural Science Foundation,ChinaProject(P2019G002) supported by the Science and Technology Research and Development Program of China RailwayProject(2019YJ193) supported by the State Key Laboratory for Track Technology of High-speed Railway,China。
文摘Bridges crossing active faults are more likely to suffer serious damage or even collapse due to the wreck capabilities of near-fault pulses and surface ruptures under earthquakes.Taking a high-speed railway simply-supported girder bridge with eight spans crossing an active strike-slip fault as the research object,a refined coupling dynamic model of the high-speed train-CRTS III slab ballastless track-bridge system was established based on ABAQUS.The rationality of the established model was thoroughly discussed.The horizontal ground motions in a fault rupture zone were simulated and transient dynamic analyses of the high-speed train-track-bridge coupling system under 3-dimensional seismic excitations were subsequently performed.The safe running speed limits of a high-speed train under different earthquake levels(frequent occurrence,design and rare occurrence)were assessed based on wheel-rail dynamic(lateral wheel-rail force,derailment coefficient and wheel-load reduction rate)and rail deformation(rail dislocation,parallel turning angle and turning angle)indicators.Parameter optimization was then investigated in terms of the rail fastener stiffness and isolation layer friction coefficient.Results of the wheel-rail dynamic indicators demonstrate the safe running speed limits for the high-speed train to be approximately 200 km/h and 80 km/h under frequent and design earthquakes,while the train is unable to run safely under rare earthquakes.In addition,the rail deformations under frequent,design and rare earthquakes meet the safe running requirements of the high-speed train for the speeds of 250,100 and 50 km/h,respectively.The speed limits determined for the wheel-rail dynamic indicators are lower due to the complex coupling effect of the train-track-bridge system under track irregularity.The running safety of the train was improved by increasing the fastener stiffness and isolation layer friction coefficient.At the rail fastener lateral stiffness of 60 kN/mm and isolation layer friction coefficients of 0.9 and 0.8,r
文摘使用32位微控制器MPC5604开发了车辆电子稳定性控制系统的电子控制单元(Electronic Control Unit,ECU)。建立了七自由度车辆模型,并制定了基于横摆角速度门限值的控制策略;选择双移线工况作为仿真工况,运用Matlab/Simulink软件实现离线仿真分析,同时通过台架试验,对比了32位控制器及16位控制器的系统运行代码时间。离线仿真结果及台架反馈的信息表明,所建立的车辆稳定性控制系统能够较好地提升极限工况下汽车的操纵稳定性,同时32位微控制器能使系统整体性能得到提升,为更加复杂的算法应用提供了扩展的空间。
