| Abstract: | Slope failure due to improper excavation is one of common engineering disasters in China. To explore the failure mechanism of soil slope induced by toe excavation, especially to investigate the influence of excavation unloading path and rate on slope stability, a numerical slope model was built via particle flow code PFC2 D. The development of crack and strain during excavation were obtained and used to evaluate the deformation characteristics.Furthermore, excavation types representing different unloading paths and rates were compared in terms of crack number and strain level. Results indicate that crack number and strain level induced by horizontal column excavation are much greater than those of vertical column excavation and oblique excavation.The crack number and strain level increase with excavation unloading rate. Besides, the feasibility of taking the average strain of slope surface and the average value of maximum strain along monitoring lines to represent the global deformation characteristics were discussed. This study can provide a theoretical guidance for slope monitoring and preliminary optimal selection of excavation scheme in the design and construction of slope engineering. |
