Dynamic response parameters of railway ballast-subgrade

Load acted on the surface of ballast was obtained through the vehicle-rail-ballast model. Dynamic computational model for railway ballast-subgrade was established through a coupling of finite elements and infinite elements method. Under train loads, the vibration acceleration and dynamic displacement in ballast-subgrade, which are of different ballast thickness and subgrade stiffness, were obtained in conjunction with Newmark integration scheme. The computational results show that the ballast thickness has evident impact on the dynamic response of subgrade, but the subgrade's impact is not as evident as the ballast thickness's impact. 1 tab, 8 figs, 9 refs.