重载列车作用下隧底结构动力响应分析  

Analysis of Dynamic Response of Tunnel Bottom Structure Under the Action of Heavy-Load Trains

作　　者：马涛[1] MA Tao(China Railway Siyuan Survey and Design Group Co.Ltd.,Wuhan Hubei 430063,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,湖北武汉430063

出　　处：《铁道建筑技术》2023年第4期148-150,185,共4页Railway Construction Technology

基　　金：中国国家铁路集团有限公司重大课题项目(2014G005-A)。

摘　　要：重载列车作用会导致铁路隧道基底结构动力响应不断增大,从而使基底结构产生破坏。采用数值模拟方法,建立单、双线隧道-围岩耦合计算模型,对重载列车作用下单、双线隧道动力响应随深度变化规律进行研究,对列车轴重、行车速度和填充层厚度对隧底结构动力响应特性的影响规律进行计算分析。结果表明:隧道横断面上的拉应力沿深度方向先增大后减小,在初支部位达到峰值,单线隧道轨下断面为最不利断面,双线隧道中线断面为最不利断面;随轴重增加,隧底仰拱各特征点竖向位移及填充层最大主应力响应均呈现线性变化趋势;随列车速度增加,各特征点竖向位移略有增大,但幅值变化不大;随填充层厚度增加,隧道仰拱最大加速度及最大主应力均呈减小趋势。The action of heavy-load trains leads to increasing dynamic response in the railroad tunnel substructure,which causes damage to the tunnel substructure.A numerical simulation method was used to establish a single-and two-lane tunnelsurrounding rock coupling calculation model to study the dynamic response of single-and two-lane tunnels with the change of depth under the action of heavy-load trains.The influence of train axle weight,travel speed and fill layer thickness on the dynamic response characteristics of the tunnel bottom structure was calculated and analyzed.The results show that:the tensile stress in the tunnel cross-section increases first and then decreases along the depth direction,reaching the peak at the initial support,with the most unfavorable cross-section in the under-rail section of the single-line tunnel and the most unfavorable cross-section in the mid-line section of the double-line tunnel;with the increase of the axle weight,the response of the vertical displacement and the maximum principal stress of the fill layer at each characteristic point of the elevation arch of the tunnel bottom show a linear trend;with the increase of the train speed,the vertical displacement of each characteristic point increases slightly,but the magnitude does not change much;With the increase of the fill layer thickness,the maximum acceleration and maximum principal stress of the tunnel arch show a decreasing trend.

关 键 词：重载列车 动力响应 轴重 列车速度 填充层厚度 

分 类 号：U451.3[建筑科学—桥梁与隧道工程]