关键词: 降雨, 边坡稳定性, 风荷载, 湿润锋, 滑坡

Abstract: Landslides frequently occur in heavily vegetated areas of southeast Fujian Province due to typhoon rainstorms. Investigating the failure mechanisms and evolution patterns of landslides influenced by vegetation, rainfall, and strong winds is crucial for disaster mechanism, monitoring, and early warning of typhoon-induced landslides in densely vegetated regions. This study focuses on the Yangxie landslide in Yongtai County, Fujian Province, investigating response patterns and analysis methods for vegetated slope stability under wind-driven rain conditions. Pulling tests on moso bamboo and single-ring infiltration tests were conducted, integrating the Green-Ampt model and infinite side slope model. Detailed main results include: 1) Bamboo’s maximum wind resistance ranges from 18 m/s to 30 m/s, corresponding to wind forces of 8 to 11. 2) Soil infiltration capacity in the windward area increases with wind speed, remaining constant at 0–12 m/s but rising rapidly beyond 12 m/s. 3) The wetting front’s migration speed in the root-soil zone accelerates with increasing wind speed and rainfall. Typhoons disturb soil by swaying vegetation to create preferential flow, mainly accelerating the wetting front’s migration speed. Wind speed significantly impacts soil infiltration capacity under wind, rain, and vegetation interactions. 4) During typhoon rainstorms, wind loads enhance rainfall infiltration in the root-soil zone through vegetation, thereby speeding up the wetting front’s migration. This process is critical for typhoon-induced landslide occurrence and development.

Key words: rainfall, slope stability, wind loads, wetting front, landslide