Abstract: Deformation of excavation slope can lead to the deformation or even destruction of its nearby buildings, threatening the safety of people’s life and assets. An effective way to prevent such accidents is to have adequate knowledge of the deformation and damage characteristics, along with the inducing factors. Herein we took the excavation slope at the Cultural Square in Badong county as an example, and investigated the site’s external dynamic conditions, inspected the spatial distribution and morphological characteristics of the surface fissures and analyzed its development patterns and mechanical characteristics. The study shows that the complex engineering geological conditions and weak geological environment are internal factors that lead to the deformation of the foundation pit slope; while the excavation is the major external dynamic factor that induces fissures, and precipitation intensifies the deformation of the excavation slope. Furthermore, FLAC software was used to verify the influence of excavation process and precipitation on ground surface deformation, which is consistent with the site investigation result. Finally, corresponding prevention measures are put forward.

Key words: foundation pit slope, ground crack, excavation process, precipitation, FLAC