The dynamic responses characteristics of colluvial landslide based on model test

Abstract

Based on shaking table model test to study the colluvial landslide caused by Yushu earthquake, the deformation and instability process of the colluvial landslide under different earthquake components and intensities were studied, the dynamic response characteristics are analysed. The results show that the permanent deformation of colluvial landslide under the strong earthquake is one of the important factors causing geological disasters. The top of the landslide appears to have a series of tensile cracks and shear fractures at first, with the increasing of seismic intensity, those cracks develop from front to back gradually, the arc fissures in the middle of the slope develop continuously and lead to subsidence and the potential slip surface extends from shoulder to the slop toe. The peak ground acceleration (PGA) and earth pressure and acceleration Fourier spectra are found to increase with the increasing of the elevation and intensity, the effects of different lithology associations on the acceleration response rules also vary with the different excitation directions. PGA amplification factors present obvious non-linearity characteristics and the variation trend is inversely proportional to the intensity. The influence of vertical component of seismic on the PGA amplification factors of landslide is slightly greater than horizontal.