移动荷载作用下离散支承浮置板轨道振动响应研究  

Vibration response of discretely supported floating slab track under a moving load

作　　者：黄强 黄宏伟[1,2] 张冬梅[1,2] HUANG Qiang;HUANG Hongwei;ZHANG Dongmei(Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China;MOE Key Lab of Geotechnical and Underground Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学土木工程学院地建下筑与工程系,上海200092 [2]同济大学岩土及地下工程教育部重点实验室,上海200092

出　　处：《振动与冲击》2018年第19期190-197,共8页Journal of Vibration and Shock

基　　金：国家重点基金项目(51538009)

摘　　要：浮置板轨道作为一种有效减振方式在城市轨道交通中获得了广泛的应用。将浮置板分别视为质量块、Euler梁和短梁,利用振型叠加法得到了三种离散支承浮置板轨道模型的振动方程,并采用Runger-Kutta法求解其响应结果。计算结果表明,将浮置板等效为质量块和长梁是浮置板轨道模型的两种极端情况,实际浮置板轨道模型计算结果介于这两个计算模型之间。浮置板存在一个临界长度,此时长梁-短梁模型和双长梁的结果基本一致。当浮置板长度很短时(0~0. 6 m),浮置板可以等效为质量块;当浮置板较长时(大于临界长度),可以整体等效为长梁;浮置板为有限长度短梁时,随着浮置板长度的增加,钢轨的挠度和浮置板支承内力会逐渐减少。对浮置板减振特性分析表明,增加浮置板长度、增加钢轨扣件刚度、增加浮置板抗弯刚度、减少浮置板支承刚度是改进浮置板减震性能和行车舒适性的有效办法。Floating slab track as an effective means is widely applied in urban rail transportation to reduce train-induced vibration.Here,a floating slab was simplified as a mass,an infinite Euler beam and a short beam,respectively.Three dynamic equations for a discretely supported floating slab track were derived using the mode superposition method,respectively.Its vibration responses were numerically solved with Runge-Kutta method.The calculation results showed that a floating slab modeled as a mas or an infinite beam are two extreme cases of a floating slab track model,the calculation result of the actual floating slab track model is between those of the two extreme track models;a floating slab has a critical length,when its length is equal to the critical one,the response result of the long beam-short beam model agrees well with that of the two-long beam model;when the length of a floating slab is very short(0-0.6 m),the floating slab can be modeled as a mass;when its length is larger than its critical length,it can be modeled as a long beam;when a floating slab is a short beam with a finite length,rail deflection and bearing force of the slab decreases with increase in the slab length.The vibration reduction characteristics analysis for floating slabs showed that increasing floating slab length,stiffness of rail pad,and flexural stiffness of floating slab or decreasing floating slab’s support stiffness is an effective method to improve its vibration reduction performance and train running comfort.

关 键 词：浮置板轨道 振型叠加法 浮置板长度 钢轨挠度 浮置板支承内力 

分 类 号：TU92[建筑科学—建筑设计及理论]