Analysis of the stability and sensitivity of slope reinforcement using combined root piles and prestressed piles

Currently, limited research exists on the joint reinforcement of slopes using root piles and prestressed piles, which is crucial for assessing stability and sensitivity. This study focuses on the Kuihe slope reinforcement project in Xuzhou. Employing the strength reduction method, a numerical model is developed using FLAC3D software to analyze the slope stability, stress, and deformation of piles. A comparative analysis is conducted among three schemes: prestressed piles, root piles, and no reinforcement. Additionally, an orthogonal test investigates the sensitivity of factors influencing slope stability after joint reinforcement. The findings reveal that the safety factor of the combined reinforcement of root piles and prestressed piles is 2.4355, lower than the horizontal displacement of the slope and supporting pile in other schemes, indicating superior reinforcement effectiveness. The potential sliding surface of the slope, when reinforced by the combination of root piles and prestressed piles, lies deep within the soil-rock junction at the slope's base, with the prestressed piles primarily bearing the sliding force. The sensitivity order of the slope safety factor to influencing factors, in the case of joint reinforcement with root piles and prestressed piles, is as follows: side length of prestressed pile > root pile length > distance between prestressed piles > length of prestressed pile > distance between root piles > diameter of root pile. These research outcomes offer valuable insights for similar engineering designs.