Vibration Response Characteristics and Application of Existing Railway Subgrade

Abstract

The existing conventional methods of subgrade disease assessment are not suitable for the existing lines. There are many research studies on the vibration response and attenuation law of the railway subgrade, but few research studies focus on the vibration response and attenuation law caused by the weak subgrade. In this study, vibration response tests were carried out at different positions and depths of the subgrade before and after reinforcement improvement. The results show that vibration response near the ballast is obvious, and it attenuates with the increase of the horizontal distance from the rail; the vibration acceleration response of the subgrade after reinforcement changes greatly; the vibration response curve of the reinforced section is spindle shaped, and the vertical vibration acceleration response attenuates obviously at the depth of 6.5 m, only about 10% to 30% of the surface; the vibration acceleration of the subgrade with reinforcement at the depth of 4.5 m attenuates to 60% of the surface; the vibration acceleration of the subgrade without reinforcement at the depth of 4.5 m attenuates to 50%–60% of the surface.

Dynamic Response Characteristics of Railway Subgrade Using a Newly-Developed Prestressed Reinforcement Structure: Case Study of a Model Test

“…In railroad infrastructures, the subgrade plays a critical part in the track stiffness and degradation of the track geometry [ 32 ]. The vibration acceleration response analysis is generally employed as an important detection index to assess the dynamic stability of the subgrade under repeated train loads [ 30 , 31 , 33 , 34 ]. Therefore, it is also necessary to understand the effect of PRS on the subgrade dynamic acceleration response and the long-term behavior under moving train loads, which is helpful for the optimization design of prestressed subgrade.…”