车-隧耦合条件下围岩对系统动力特性的影响

Influence of Surrounding Rock Grades on the System Dynamic Properties under the Vehicle-tunnel Coupling

随着地铁和城际高铁等城市公共交通的迅速发展,有关车辆-隧道体系的动力相互作用和有关围岩条件与结构系统的关系研究日显重要。本文首先将轨道/隧道作为参振子结构纳入车辆计算模型,考虑车-隧体系耦合动力作用,建立了车-隧耦合动力分析模型。在此基础上,主要从能反映车辆运行品质和隧道/轨道结构设计参数或动力特性的一些主要指标入手(比如车体竖向振动加速度、车辆动轮重、轮重减载率、钢轨的竖向位移、隧道围岩顶部的竖向位移和竖向应力等),探讨了模型分析、单元类型、指标确定等问题,研究分析了不同围岩级别对系统动力特性的影响。分析表明:只要隧道结构/轨道结构设计合理,车辆选型合理并在一定的车速范围内,各类围岩条件均能满足车-隧系统的动力特性要求。但综合各项指标的设计标准,Ⅲ级围岩各项指标相对较优。

With the rapid development of subway and inter-city elevated trains as a means of urban transport, the study of both the dynamic interaction of vehicle-tunnel system and how the surrounding rock and track structure are related to each other is becoming increasingly important. This paper has first included track-tunnel as a parametric substructure in the vehicle calculation model and, while taking into account the vehicle-tunnel coupling, to set up a dynamic analysis model of vehicle-tunnel coupling, and then, from some main indices （ such as car body vertical vi- bration acceleration, vehicle dynamic wheel weight, wheel load reduction rate, rail vertical displacement, vertical displacement and vertical stress of surrounding rock above tunnel ） that best reflect the quality of a running vehicle, the design parameters of tunnel-track structure and/or dynamic properties, it has probed into such problems as model- ing analysis, element types and index determination, and studied the effect of various grades of surrounding reck on the dynamic properties of the structural system. The analysis shows that, so long as the structural designs of tunnel and track, the selection of the vehicle type and the running speed are rational, the conditions of all grades of sur- rounding rock can satisfy the requirements of the dynamic properties of the vehicle-tunnel system; with design criteria for all indices taken into account, those for surrounding rock III are the best.