川北某变电站堆积体边坡稳定性及加固措施分析  

Analysis on stability and reinforcement measures of accumulation body slope in a substation in north Sichuan

作　　者：李海涛 任光明[1] 范荣全 曾文慧 董斌 LI Haitao;REN Guangming;FAN Rongquan;ZENG Wenhui;DONG Bin(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China;State Grid Sichuan Economic Research Institute,Chengdu 610041,China)

机构地区：[1]地质灾害防治与地质环境保护国家重点实验室(成都理工大学),成都610059 [2]国网四川省电力公司经济技术研究院,成都610041

出　　处：《成都理工大学学报（自然科学版）》2023年第4期454-464,共11页Journal of Chengdu University of Technology: Science & Technology Edition

摘　　要：为解决山区变电站建设过程中基坑周边的堆积体边坡稳定性和设计优化问题,以川北某变电站基坑高边坡为例,结合监测数据,采用FLAC 3D对该边坡各阶段暴雨工况进行数值反演,揭示其应力、塑性区、位移和稳定性规律,定量评价支护措施的作用效果,并模拟改进的支护方法,以期选取最优方案。结果表明:降雨入渗堆积体及后缘拉裂缝,加剧了软弱滑动面的贯通趋势;于露空区增设抗滑桩与腰梁,最大位移监测值与模拟值较初期支护分别减小74.7%和67.8%,其挠度曲线存在明显拐点;采用预应力锚杆加固土体,安全系数从1.06回升至1.41,支护效果提升较明显。对于堆积体边坡,降雨是其失稳的主要影响因素,可施加预应力锚杆以改变边坡牵引破坏模式,提供抗拉承载力,降低雨水入渗影响,有效控制坡体变形。This paper presents the study of the stability and design optimization of the accumulation body around the high slope of foundation pit of a substation in northern Sichuan.According to the monitoring data,FLAC 3D is used to conduct numerical inversion of the rainstorm conditions at various stages of the slope,so as to reveal the laws of stress,plastic zone,displacement and stability,quantitatively evaluate the effect of supporting measures,simulate the improved supporting methods,and select the best engineering scheme.The results show that the penetration tendency of the weak sliding surface is intensified by the rainfall infiltrated in the accumulation body and in the tensile crack at the back edge.When anti-slide pile and waist beam are added in open area,the maximum displacement monitoring value and simulated value decrease by 74.7%and 67.8%respectively compared with the initial support,and the deflection curve has obvious inflection point.The supporting effect is obviously improved when pre-stressed anchor bolt is used to strengthen the soil,and the safety factor rises from 1.06 to 1.41.It is recognized that rainfall is the main influencing factor of slope instability of accumulation body.The use of pre-stressed anchor can change the traction failure mode of the slope,provide tension capacity,reduce the influence of rainwater infiltration,and effectively control the slope deformation.

关 键 词：堆积体边坡 监测数据 数值反演 边坡防治 支护方案 

分 类 号：TU43[建筑科学—岩土工程]