Back-analysis of Donghekou landslide using improved DDA considering joint roughness degradation

摘要: Currently, the dynamic behavior of high-speed long-runout landslides triggered by earthquakes remains unclear due to complexity such phenomena. Degradation in shear strength rock masses is considered a primary factor contributing high velocities and long runout distances these landslides. In this study, degradation induced changes joint morphology analyzed considering numerical model Donghekou landslide, using discontinuous deformation analysis (DDA). First, an exponential roughness function (i.e., JRCm) that depends on displacement incorporated with nonlinear Barton–Bandis (B–B) criterion, modified B–B criterion combined DDA. Moreover, virtual introduced DDA propagation cracks intact masses, order simulate phenomenon earthquake-induced Subsequently, improved (IDDA) validated via simulations test sliding block over inclined plane. Finally, IDDA employed which was 2008 Wenchuan earthquake China. Furthermore, entire process including crack propagation, instability, initiation, motion, depicted. The simulated deposit patterns obtained are good agreement results field investigations. simulation also prove can reflect key movement behaviors landslide joints significantly influences distance velocity mass.