工程扰动诱发川西杜米滑坡复活变形特征及机理分析  

Reactivation Characteristics and Mechanism of Engineering Disturbed Dumi Landslide in Western Sichuan Province,China

作　　者：周洪福[1] 方甜 夏晨皓 冉涛 徐如阁[1] 张景华[1] ZHOU Hongfu;FANG Tian;XIA Chenhao;RAN Tao;XU Ruge;ZHANG Jinghua(Chengdu Center,China Geological Survey,Chengdu,Sichuan 610081,China;College of Earth Science and Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590,China;Nuclear Industry Southwest Geotechnical Investigation and Design Institute Co.Ltd.,Chengdu,Sichuan 610061,China)

机构地区：[1]中国地质调查局成都地质调查中心,四川成都610081 [2]山东科技大学地球科学与工程学院,山东青岛266590 [3]核工业西南勘察设计研究院有限公司,四川成都610061

出　　处：《现代地质》2023年第4期1044-1053,共10页Geoscience

基　　金：中国地质调查局项目(DD20211379);第二次青藏高原综合科学考察研究项目(2019QZKK0904);四川省重点研发项目(2020YFS0296)。

摘　　要：人类工程活动是诱发滑坡复活并导致滑坡整体或局部失稳破坏的重要因素之一。本文以川西雅江县杜米滑坡为例,通过地质调查、Insar监测、工程钻探、数值分析、稳定性计算等技术方法,在查清滑坡特征的基础上,总结滑坡变形破坏特征并进行分区评价,剖析滑坡复活变形成因机理,探讨滑坡前缘坡脚开挖程度与滑体稳定性之间的关系。研究结果表明,杜米滑坡一共发育3个滑面,分别对应强烈变形区、中等变形区和轻微变形区。前缘坡脚开挖是诱发杜米滑坡复活的主要原因,降雨入渗导致滑带土强度劣化是助推因素。前缘坡脚开挖水平深度超过10 m,暴雨工况滑体将出现明显变形下滑破坏。研究成果对避免类似杜米滑坡导致的“小灾大损”具有较强的参考和借鉴意义。Human engineering activities are an important factor that induce the reactivation and instable failure of landslides.In this study,taking the Dumi landslide in Yajiang County in Sichuan Province as an example,we summarize the deformation and failure characteristics and zoning evaluation,based on the Dumi landslide characteristics investigation by field investigation,Insar interpretation,engineering drilling,numerical analysis,and stability calculation.We analyzed the formation mechanism of the Dumi landslide reactivation,and the relationship between the stability coefficient FOS and excavation distance to the toe of the Dumi landslide.The results show three sliding surfaces,corresponding to strong,medium,and weak deformation areas.Slope toe excavation is the main trigger for the reactivation of the Dumi landslide,and a consequent deterioration in the shear strength of sliding zone soil caused by rainfall infiltration is the boosting factor.When the horizontal excavation distance at the slope toe is over 10.0 m,the sliding body would be clearly deformed and damaged under rainstorm conditions.Our results have good reference significance for avoiding small geological disasters in generating large losses,caused by landslides similar to that at Dumi.

关 键 词：工程扰动 滑坡复活 稳定性分析 成因机理 

分 类 号：P642.22[天文地球—工程地质学]