Due to the limitations of railway route selection,some high-speed railways are inevitably built near or across fault zones.To study the distribution of rail-bridge interaction under different load history states of su...Due to the limitations of railway route selection,some high-speed railways are inevitably built near or across fault zones.To study the distribution of rail-bridge interaction under different load history states of suspension bridges under three types of near-fault pulse-type earthquakes,this paper takes China’s longest high-speed railway suspension bridge—Wufengshan Yangtze River Bridge-as the background and establishes a spatial model of the rail-bridge interaction of a suspension bridge.The results show that:under the constant load state,the distribution of additional force under three types of pulse-type earthquakes is generally consistent,and pulse-type earthquakes produce more significant responses than non-pulse-type earthquakes;with fling-step pulse being the largest,it is advised to specifically consider the influence of the fling-step pulse in the calculation.Under the initial condition of the main beam temperature loading history,all rail-bridge additional forces increase significantly,particularly affecting the steel rail system.The value of the rail-bridge interaction additional force under the near-fault earthquake in the initial state of the suspension bridge when the train deflection load is loaded from the tower to the mid-span is more significant and particularly unfavourable.The initial effect of the braking load will weaken the effect of the deflection load loading history.The results of the study indicate that the effect of the initial state of suspension bridges is an important factor influencing the rail-bridge interaction under near-fault pulse-type earthquakes,which needs to be considered in future seismic design.展开更多
文摘针对高速铁路出现牵引网网压低频振荡导致多个动车所的多台动车组牵引封锁现象,首先建立动车组线侧脉冲整流器状态空间模型;其次对动车组整流器设计了一阶非线性自抗扰控制器(active disturbance rejection control,ADRC)来替换传统的基于线性比例-积分(proportional integral,PI)控制器的瞬态电流控制策略(transient current control strategy,TCCS);随后从设置过渡过程,计算扩张状态观测器等方面展开,将外界扰动和系统内部扰动归算为总扰动,并给出相应的动态非线性补偿;最后,在Matlab/Simulink平台上搭建基于传统PI控制器和基于ADRC控制器的TCCS的双重化整流器模型,对比分析后得出ADRC控制具有更强的鲁棒性结论。为进一步验证ADRC控制效果,还将该仿真模型接入牵引网系统链式仿真模型中,发现该控制策略在具有较强鲁棒性和对参数不敏感性的同时,对牵引网网压低频振荡过电压有着较好的抑制效果。
基金Supported by grants from the Hunan Pro vince Inno vation Plat-form and Talent Plan Project(Grant No.2021RC3017).
文摘Due to the limitations of railway route selection,some high-speed railways are inevitably built near or across fault zones.To study the distribution of rail-bridge interaction under different load history states of suspension bridges under three types of near-fault pulse-type earthquakes,this paper takes China’s longest high-speed railway suspension bridge—Wufengshan Yangtze River Bridge-as the background and establishes a spatial model of the rail-bridge interaction of a suspension bridge.The results show that:under the constant load state,the distribution of additional force under three types of pulse-type earthquakes is generally consistent,and pulse-type earthquakes produce more significant responses than non-pulse-type earthquakes;with fling-step pulse being the largest,it is advised to specifically consider the influence of the fling-step pulse in the calculation.Under the initial condition of the main beam temperature loading history,all rail-bridge additional forces increase significantly,particularly affecting the steel rail system.The value of the rail-bridge interaction additional force under the near-fault earthquake in the initial state of the suspension bridge when the train deflection load is loaded from the tower to the mid-span is more significant and particularly unfavourable.The initial effect of the braking load will weaken the effect of the deflection load loading history.The results of the study indicate that the effect of the initial state of suspension bridges is an important factor influencing the rail-bridge interaction under near-fault pulse-type earthquakes,which needs to be considered in future seismic design.
