Characteristics and Stability Analysis of Collapse Body in Hetian Village, Longshan Town, Fogang County, Guangdong Province

Fogang County, Guangdong Province is located in the northern part of Guangdong Province, one of the three heavy rainstorm centers in Guangdong Province. Collapse geological disasters induced by heavy rainfall are extremely developed in the area. To guide the prevention and control of similar geological disasters in the area, this study has carried out field investigations and the red plane polar projection method, combined with the high-density electrical method and seismic surface wave method to investigate the geological characteristics, causes, and stability of the collapse in Hetian Village, Longshan Town, Fogang County. Through analyzing the geological and environmental characteristics of the collapse body based on its terrain and landforms, the collapse body should have been piled up on the slope surface, with a high and steep slope, as well as an extremely unfavorable geological environment. The high-density electrical and seismic surface wave methods showthe characteristics of the collapse body interpreted through geophysical exploration. The surface part of the collapse body has already started collapsing, forming a loose layer with a high porosity and deteriorating stability, meanwhile softened by water, making it prone to collapse. A comprehensive analysis of the mechanism of collapse formation and conduct stability has been conducted. The following conclusions are drawn: (1) Slope-cutting for building houses is the dominant factor in the occurrence of collapse; (2) The characteristics of the rock and soil mass on the slope are inherent to collapse formation; (3) Rainfall is a direct trigger for the geological hazards; (4) The collapse body is still in an unstable state with serious potential danger; (5) It is recommended that the slope be protected and stabilized by chipping and load shedding, surface drainage, and construction of retaining walls, as well as increased monitoring.