高速铁路不同形式的路基过渡段动力特性分析

高速铁路路基过渡段包括正梯形和倒梯形两种过渡形式。为评价不同过渡段形式对车辆-轨道-路基过渡耦合系统动力特性的影响，基于车辆-轨道-路基耦合力学原理，运用MATLAB计算程序建立了列车-轨道-路基过渡段垂向耦合动力模型。计算结果表明:正梯形路基过渡段形式的刚度变化在纵向和深度方向比倒梯形过渡段形式更平缓，更有利于高速列车行驶的安全和平顺；过渡段3 m范围内系统动力响应变化较为剧烈，在过渡段尺寸及形状均匀段两种过渡段形式下系统动力响应无差异，在过渡段尺寸及形状变化范围内，系统动力响应表现出一定差异，且正梯形过渡段形式下动力响应波动较小。

Analysis on the Dynamic Performance of Different Subgrade Transition Sections in the High Speed Railway

Two kinds of transition sections including trapezoid and inverted trapezoid transition sections have been suggested for high speed railways on slab tracks. In order to evaluate the influence of the two transition section structures to the dynamic performance of the vehicle-track-subgrade coupling system, a vertical coupled dynamic model of vehicle-track-subgrade transition section is established based on the coupling mechanics principle and using MATLAB program. The results show that the dynamic response of the trapezoid transition section is better than that of the inverted trapezoid transition section, which is more favorable to maintain the safety and harshness of the vehicle. The dynamic response changes abruptly after the first 3 m of the subgrade transition section. In addition, there’s no difference of the dynamic response in the uniform region, however, that is become bigger in the nonuniform and the trapezoid transition section is in a smaller change in dynamic response.