Failure parameter inversion of the Baige landslides based on seismic signal analysis
摘要
Southwest China is prone to landslide disasters due to the complex geographical condition. The failure parameters of two Baige landslides in 2018 were inversed based on seismic signals recorded at adjacent seismograph stations. The global crustal one-dimensional average velocity model provided by Crust 1.0 was adopted to calculate Green’s function. Then, the force‒time functions of the two Baige landslides were inversed. Based on the landslide motion model, the kinetic motion parameters of the two Baige landslides were calculated, and the disaster processes of the two Baige landslides were ultimately revealed in this study. The results showed that the duration of the first Baige landslide was approximately 130 s, including three stages, i.e., the collapse and slide stage of the main sliding mass (last 44 s), the crushing and disintegration stage (last 47 s), and the scattering and accumulation stage (last 39 s). The duration of the second Baige landslide was approximately 130 s, including the collapse and slide stage (last 32 s), the crushing and disintegration stage (last 46 s) and the scattering and accumulation stage (last 58 s). The maximum force is 1.65 × 1011 N in for the first Baige landslide and 1.69 × 1011 N for the second Baige landslide, respectively. The maximum velocity of the centroid reached 65.3 m/s at t = 44 s for the first Baige landslide, while the maximum velocity of the centroid reached 64.9 m/s at t = 32 s for the second Baige landslide, which are larger than the existing simulation results. The calculated displacement matches the actual terrain based on the historical satellite images after the two Baige landslides. The trajectory angles of the centroids of the two landslides ranged from 4°~34° and 1°~51°, respectively, and the sliding friction coefficient ranged from 0.03 ~ 0.95 and 0.05 ~ 1.24, respectively. This study provides an indirect method for measuring landslide parameters, and a seismological basis and references for studying the failure mechanism of large-scale landslides.