卸荷损伤效应下开挖边坡稳定性极限平衡分析  

LIMIT EQUILIBRIUM ANALYSIS ON THE STABILITY OF EXCAVATION SLOPE UNDER UNLOADING DAMAGE EFFECT

作　　者：邓东平[1] 石柱 彭文耀 DENG Dongping;SHI Zhu;PENG Wenyao(College of Civil Engineering,Central South University,Changsha 410075,China;Hunan Road and Bridge Construction Group Co.,Ltd.,Changsha 410000,China;Hunan Pingyi Expressway Construction and Development Co.,Ltd.,Yueyang 414517,China)

机构地区：[1]中南大学,土木工程学院,长沙410075 [2]湖南路桥建设集团有限责任公司,长沙410000 [3]湖南省平益高速公路建设开发有限公司,岳阳414517

出　　处：《工程地质学报》2025年第1期327-340,共14页Journal of Engineering Geology

基　　金：国家自然科学基金项目(资助号:52278380);湖南省自然科学基金项目(资助号:2023JJ30670);湖南省交通运输厅科技项目(资助号:202008).

摘　　要：边坡开挖卸荷在一定程度上会引起坡体内岩土体强度产生损伤,进而影响到开挖边坡稳定性。当前,边坡工程开挖滑塌事故频有发生,而较少研究关注卸荷损伤效应下开挖边坡稳定性分析。在此,基于简单的线性模型,建立开挖卸荷效应下边坡滑面岩土体强度参数计算公式。进而,结合极限平衡推力法,引入迭代计算策略,实现边坡安全系数反馈与滑面强度参数更新之间的交互计算,达到卸荷损伤效应下开挖边坡稳定性分析的目的,为工程边坡开挖过程中安全状态评估提供科学依据。此后,经3种不同类型开挖边坡算例对比分析,验证了本文方法的可行性。研究表明,开挖卸荷损伤明显降低开挖后边坡稳定性,且边坡破坏形态可能会演变成近坡面的浅层失效。The excavation and unloading behavior may cause damage to the strength of the geotechnical body in the slope,and then affect the stability of the excavation slope.At present,the slope sliding accidents occur frequently during slope excavation,but few researches pay attention to the stability analysis of slope under unloading damage effect.Based on the simple linear model,this work established the calculation formula of the strength parameters of the geotechnical body on the slip surface under the excavation unloading effect.Furthermore,combined with the limit equilibrium thrust method,the iterative solution strategy is introduced to realize the interactive calculation between the feedback of the slope factor of safety and the update of the strength parameters of the geotechnical body on the slip surface,so as to achieve the purpose of the stability analysis of the excavation slope under the unloading damage effect.Thereby,this work provides a scientific basis for the safety state assessment in the process of engineering slope excavation.Thereafter,the feasibility of the proposed method is verified by the comparison and analysis of three different types of slope excavation examples.The results show that the excavation unloading damage significantly reduces the stability of the slope after excavation,and the failure pattern of the slope may evolve into the shallow failure near the slope surface.

关 键 词：开挖边坡稳定性 卸荷损伤 滑面强度参数 极限平衡推力法 安全系数 滑动面 

分 类 号：P642.2[天文地球—工程地质学]