Hydrological response characteristics of landslides under typhoon-triggered rainstorm conditions

Abstract

ABSTRACT: Many landslide disasters, which tend to result in significant damage, are caused by typhoon-triggered rainstorms. In this case, it is very important to study the dynamic characteristics of the hydrological response of landslide bodies since it enables the early warning and prediction of landslide disasters in typhoon periods. To investigate the dynamic mechanisms of groundwater in a landslide body under typhoon-triggered rainstorm conditions, the authors selected the landslide occurring in Zhonglin Village, Wencheng County, China (also referred to as Zhonglin Village landslide) as a case study. The transient seepage field characteristics of groundwater in the landslide body were simulated with two different rainfall models by using the finite element method (FEM). The research results show that the impact of typhoon-triggered rainstorms on landslides can be divided into three stages: (i) Rapid rise of groundwater level; (ii) infiltration of groundwater from the surface to deeper level, and (iii) surface runoff erosion. Moreover, the infiltration rate of groundwater in the landslide body is mainly affected by the intensity of typhoon-induced rainfall. It can be deduced that higher rainfall intensity leads to a greater potential difference and a higher infiltration rate. The rainfall intensity also determines the development mode of landslide deformation and destruction.

Keywords

• Typhoon-triggered rainstorm
• Landslide
• Seepage
• Hydrological response
• Hydrogeological survey engineering
• Geological disaster survey engineering