施工诱发边坡失稳变形机制及应急治理对策  

Deformation mechanism and urgent treatment of unstable slope induced by construction

作　　者：许锐[1] 程辉[1] 李寻昌[1] 马安锋 XU Rui;CHENG Hui;LI Xunchang;MA Anfeng(School of Geology Engineering and Geomatics, Chang’an University, Xi’an 710054, China;Xi’an Exploration Engineering Co. Ltd., Shaanxi Geology and Mineral Bureau, Xi’an 710016, China)

机构地区：[1]长安大学地质工程与测绘学院,陕西西安710054 [2]陕西省地矿局西安中勘工程有限公司,陕西西安710016

出　　处：《煤田地质与勘探》2017年第3期107-111,共5页Coal Geology & Exploration

基　　金：长安大学中央高校基本科研业务费专项资金项目(310826171013;310826161018);国家自然科学基金项目(41572261)~~

摘　　要：通过对香溪大道失稳边坡地质灾害调查,对边坡的地形地貌、地层岩性、岩体结构、原设计方案与施工过程进行研究,在此基础上通过FLAC3D数值模拟,结合工程地质条件分析,对原格构挡墙逆作法施工诱发边坡牵引式滑动过程进行了分析,并对其变形破坏机制进行深入探讨。研究结果表明:边坡变形受工程地质条件控制作用明显,边坡开挖改变了坡体原来的力学平衡条件,为边坡变形失稳创造了客观条件;由于超开挖施工,受格构挡墙自重作用,下部支撑岩体受压破坏,导致格构挡墙失稳下沉,带动其后坡体变形,形成牵引式滑动;随着坡体滑移的发展,边坡将逐渐拉裂破坏并形成贯通的剪切滑动面,从已施工的格构挡墙下部贯通剪出,最终整体失稳破坏;基于破坏机制分析的应急治理措施将重点放在为原格构挡墙下部提供有效支撑和控制潜在滑动面变形上;监测结果表明,应急治理后边坡达到稳定性要求。Based on the investigation of engineering geological hazard of an unstable slope along Xiangxi avenue,the topography and geomorphology,formation lithology,rock mass structure,original design scheme and construction process were studied in detail so as to analyze the slope deformation mechanism.A geological FLAC3D model of the unstable slope was described by engineering geological profile,and then the process of retrogressive landslide due to top-down construction of lattice retaining wall was analyzed in the paper.The slope evolvement sketch of mechanism from deformation to failure was described.The results show that the slope deformation was controlled by engineering geological conditions and the change of mechanics equilibrium condition due to slope excavation,caused slope deformation and instability;because of overbreak,the damage of lower supporting rock under structural deadweight led to the lattice retaining wall subsidence,slope deformation,and retrogressive landslide;the retrogressive sliding may cause the distortion and shearing slide plane in the slope,and when the sliding plane cut through,the slope would fall;slope reinforcement based on the analysis of deformation mechanism focuses on supporting the lattice retaining wall and controlling the distortion of potential shearing exit;the monitored deformation curve indicates that the slope is stable after urgent treatment.

关 键 词：边坡工程 牵引式滑坡 逆作法施工 变形机制 应急治理 

分 类 号：TU45[建筑科学—岩土工程]