Vertical Random Vibration Analysis of Track-Subgrade Coupled System in High Speed Railway with Pseudoexcitation Method

Xinwen Yang,Xiaoshan Liu,Shunhua Zhou,Jingchao Zang,Xiaoyun Ma,Jiangang Shen

doi:10.1155/2016/7064297

Abstract

In order to reduce the ground-borne vibration caused by wheel/rail interaction in the ballastless track of high speed railways, viscoelastic asphalt concrete materials are filled between the track and the subgrade to attenuate wheel/rail force. A high speed train-track-subgrade vertical coupled dynamic model is developed in the frequency domain. In this model, coupling effects between the vehicle and the track and between the track and the subgrade are considered. The full vehicle is represented by some rigid body models of one body, two bogies, and four wheelsets connected to each other with springs and dampers. The track and subgrade system is considered as a multilayer beam model in which layers are connected to each other with springs and damping elements. The vertical receptance of the rail is discussed and the receptance contribution of the wheel/rail interaction is investigated. Combined with the pseudoexcitation method, a solution of the random dynamic response is presented. The random vibration responses and transfer characteristics of the ballastless track and subgrade system are obtained under track random irregularity when a high speed vehicle runs through. The influences of asphalt concrete layer’s stiffness and vehicle speed on track and subgrade coupling vibration are analyzed.

Highlights

Unballasted track has been extensively used in high speed railway construction in China for its high regularity, high stability, and high reliability
The random vibration response and transfer characteristics of ballastless track and subgrade system are obtained under track random irregularity when a high speed vehicle runs through
The receptance of the structure is the dynamic response of each part of the structure under a unit force, known as the dynamic flexibility of the structure

Summary

Introduction

Unballasted track has been extensively used in high speed railway construction in China for its high regularity, high stability, and high reliability. Matsuura [4, 5] studied the track-foundation dynamics responses under the simple moving harmonic loads with the green function method in Japanese Shinkansen railway, in addition, considering the layered soil influence on wave propagation. The dynamic behavior of the subgrade under the train load was studied based on the vehicle-track coupling dynamics theory and the finite element method [9,10,11,12,13]. Based on finite element method, the dynamic response of the roadbed under high speed train loads was analyzed, and the effect of the train speed, complex modulus of the subgrade, and vibrating condition of the vehicles were discussed [15]. The influences of the asphalt concrete layer’s stiffness and vehicle speed on track and subgrade coupling vibration are analyzed

The Vehicle-Track-Subgrade Coupling Dynamic Model

Equations of Motion of Track-Subgrade System

Results and Discussion

Conclusions