An improved inversion of Donghekou landslide considering 'starting-elastic-impulsive' acceleration mechanism

摘要

High-speed remote landslides have been the focus of landslide research because of their fast movement, long slidingdistance, and large damage range. This paper takes the Donghekou landslide as an example and establishes a more reasonable3D model based on high-precision DEM data. Under the premise of considering the landslide initiation mechanism,the complete dynamic process of Donghekou landslide initiation-acceleration-impact fold-deceleration accumulation isreproduced by PFC3D numerical simulation software. The numerical simulation results are consistent with the actualsituation. The results show that the Donghekou landslide took about 20 s from the moment of initiation to the moment ofimpact with the barrier, about 25 s from the start of impact with the barrier to the complete departure from the barrier,and about 19 s from the end of impact to deposition. The maximum velocity of about 58.5 m/s and the maximum displacementof about 2159.0 m are typical of ultra-high-speed remote landslides. The maximum displacement and maximumvelocity of the slide show a decreasing pattern from head to tail and from surface to base, except for the distribution ofthe maximum displacement at the head, which does not show a clear pattern. Divide the sliding mass into left and rightparts, for sliding mass with the same longitudinal position: the left side has the maximum velocity and the right side hasthe maximum displacement.