高速铁路路基动力响应中的双峰现象分析

结合我国高速客运专线铁路的发展形势,着重分析时速超过200km/h以上的路基动力响应。采用能够综合反映车辆和轨下基础因素的模拟振动荷载,通过非线性数值分析,研究了高速行车条件下路基动力响应包括横断面位移、加速度、应力随行车速度的突变或双峰现象的变化规律,探讨了路基设计参数与双峰现象的关系,并与部分实测结果进行了对比分析。还初步研究了引起这一现象的不平顺和体系共振等因素在不同车速范围的作用程度。路基动力响应的双峰现象表明,车辆和轨道基础之间存在着复杂的相互作用,这些作用同时共存,随着条件的变化,此消彼长。通过这一分析,为进一步认识高速铁路路基的动力特性和进行高速铁路轨下基础设计提供了参考。

A study on the sudden changes or double peaks in the dynamic response of subgrade of high speed railway

In connection with the development of special high speed passenger railway-lines in China,the dynamic response of railway subgrades is analyzed for train speeds over 200km/h.Using a simulated dynamic load that suitably reflects the vehicle factor and structural factor below the track and using non-linear numerical analyses,the sudden changes or double peaks are identified in the dynamic response of subgrades under high speed conditions.The study found that factors such as the resonant vibration and line irregularity are the major influence factors in various speed ranges.The calculations are compared with test results.