重载铁路隧道基底动力响应数值仿真分析

Numerical Simulation Analysis of Dynamic Response Characteristics of Tunnel Base in Heavy Load Railway

研究目的:重载列车作用下,隧道基底易出现开裂、破损等病害,严重影响行车安全。因此,研究重载列车荷载作用下隧道基底动力响应特征进而为隧道基底病害治理提供依据具有重要理论意义和实践价值。研究结论:(1)以山西中南部铁路某隧道为研究背景,采用ANSYS软件建立了重载铁路隧道基底动力响应分析模型,采用人工激励的方式模拟列车振动荷载,选用静力+动力叠加进行计算,得到了重载列车作用下隧道基底结构的荷载时程曲线;(2)分析了隧道基底竖向位移、加速度和最大主应力的时程曲线,得到了重载列车荷载作用下隧道基底结构动力响应特征;(3)选取隧道基底主要参数如矢跨比、填充层厚度、仰拱厚度和铺底厚度,通过模拟分析得到了不同参数条件下隧道基底动应力响应特征;(4)本研究成果可为重载铁路隧道基底设计和病害治理提供参考。

Research purposes: The tunnel base of heavy haul railway is prone to crack and damage, which seriously affects the railway operation safety under the action of heavy haul train. Therefore, it is of theoretical and practical significance to study the dynamic response characteristics of tunnel basement under heavy train load so as to provide the basis for controlling tunnel basement diseases.Research conclusions:(1) Taking a tunnel in South-central Shanxi Railway as the research background, the dynamic response model of tunnel foundation in heavy haul railway is established by ANSYS, the load time history curve of tunnel base structure under the action of heavy train is obtained, through using artificial excitation to simulate train vibration load, selecting the static and dynamic superposition calculation method.(2) The dynamic response characteristics of tunnel basement structure under heavy train load are obtained, by analyzing the time history curves of vertical displacement, acceleration and maximum principal stress of tunnel basement.(3) The dynamic stress response characteristics of the tunnel base under different parameters such as rise span ratio, thickness of filling layer, thickness of invert and thickness of bedding are obtained.(4) The research results can provide a reference for the design and disease control of heavy haul railway tunnel foundation.