Dynamic Response of High-Speed Train-Track System Due to Unsupported Sleepers

This paper is concerned with a numerical study on the dynamic response of a high-speed rail (HSR) system subjected to unsupported sleepers using the moving element method (MEM). A three-phase computational scheme in conjunction with the MEM is proposed to account for the motion of the unsupported sleepers in relation to the truncated rail segment in the moving coordinate system. The accuracy of the proposed computational scheme is examined by comparison with available analytical results in the literature and against the finite element method using commercial software. A parametric study is conducted using a computational model consisting of a 10-degree of freedom train model and a three-layer ballasted track model to investigate the effect of unsupported sleepers on the dynamic response of the HSR system. Various factors affecting the response of the HSR system, including the speed of the train, the number of unsupported sleepers and the distance between the unsupported sleepers, are examined and discussed.