Dynamic response and mechanical deformation properties of the soil cutting slope under train cyclic loads

Abstract

A series of large-scale geotechnical model tests and numerical simulations were carried out to study the dynamic behavior and the mechanical deformation mechanism of the railway slope subjected to train cyclic load. We investigated the frequency domain and deformation mechanism of the railway slope. It was found that the high-frequency vibrational component is greater close to the track, and the dominant frequency is concentrated in the region 35~45 Hz. Moreover, the impact of the platform width, slope ratio, and slope steps on the dynamic mechanical properties are further studied. The design parameters of slope types have a strong influence on the dynamic behavior of the railway slope under cyclic load. Under unfavorable parametric conditions, it is possible to form a cumulative tension strain band extending to the interior of the slope, which will result in a large-scale landslide. In contrast, with the optimization of the slope design parameters, when the platform width exceeds 4 m or the slope rate is in the range of 1:1.25~1:1.5, no tension strain zone appears inside the slope, and a compression strain zone easily occurs at the foot of the slope, which will form compression deformation in the shallow portion of the slope surface. It can be noticed that the attenuation rate is the maximum close to the track and reduces gradually in the far field. Besides the vibration intensity in platform area decreases, the acceleration amplitudes are attenuated by more than 70%. Optimization of the slope design parameters can effectively reduce the risk of severe large-scale sliding and improve the stability of the railway slope. Furthermore, the fluctuation effect is more noticeable as the number of slope steps increase.