Investigation of the failure mechanism and reinforcement control effect of cut slopes under climate change

Abstract

Under climate change, the increasing frequency of extreme rainfall events has made soil cut slopes more prone to progressive instability. Understanding their deformation–failure mechanisms and reinforcement effects is therefore of engineering significance. However, previous studies have mainly focused on overall stability evaluation or mechanical behavior of anti-slide piles, while the progressive displacement propagation of actual slopes and the redistribution of lateral earth pressure within the sliding mass before and after reinforcement remain insufficiently addressed. In this study, a typical cut slope in Liaoyuan City, Jilin Province, China, was investigated using field surveys, engineering drilling, laboratory tests, and rainfall data. Based on laboratory test results, a discrete element model was established using PFC software to compare the deformation evolution and lateral earth pressure response of the slope under natural conditions and after reinforcement with double-row anti-slide piles. The results show that, under natural conditions, displacement first initiates at the slope crest and then propagates toward the slope toe along the potential sliding surface, eventually forming a through-going shear band and showing clear progressive instability. The double-row anti-slide piles effectively suppress displacement propagation, prevent shear band coalescence, and transform the slope from continuous deformation to a relatively stable state. Meanwhile, reinforcement alters the transmission path of lateral earth pressure within the sliding mass, reduces earth pressure fluctuations, and shares the landslide thrust. These findings provide an engineering reference for the stability analysis and anti-slide pile design of similar cut slopes.