摘要
为了解决花马湖上湖与中湖水系连通工程的沿线边坡失稳问题,以开挖施工过程中发生的边坡失稳情况为基础,对边坡失稳机理、变形破坏特征及产生地质条件进行系统分析,提出四类边坡失稳模式,即均质蠕滑-拉裂型(Ⅰ型)、缓-中倾顺向坡滑移-拉裂型(Ⅱ型)、块体结构楔形块体剪切-滑移型(Ⅲ型)和复合型(Ⅳ型)四类,并根据每种类型的失稳主控因素提出相应的应对措施。结果表明:对于Ⅰ型边坡不宜太陡,全强风化基岩开挖坡比1∶1~1∶0.75较适宜,及时对边坡进行喷护;对于Ⅱ型边坡主要采用锚杆(索)进行系统加固和锁口处理;对于Ⅲ型是对不稳定块体及时进行加固或清除处理,加固手段主要根据块体大小可采取不同长度锚杆(索);对于Ⅳ型应结合地质地形条件找出关键边坡失稳模式,采取相应的应对措施。针对不同地质条件所采取的不同开挖坡比和锚杆支护措施,取得了较好的效果,可为类似边坡工程提供参考。
The strata along the uppermiddle lake water system connectivity project of HuamaLake are mainly composed of Yanshanian monzonite and Triassic sedimentary rock.The rock mass is strongly weathered and the fractures are developed.The height of the excavation slope of the connecting channel is from 7 m to 75 m,and the slope stability problem is prominent.In this paper,based on the slope instability occurred in the excavation construction process,the slope instability mechanism,deformation and failure characteristics and geological conditions are systematically analyzed,the slope instability mode is divided into four types by using the principle of engineering geological analysis:homogeneous or quasi-homogeneous creep sliptensile cracking type(Ⅰ),sliding-tensile cracking type of gentle-middle dip slope(Ⅱ),shearsliding type of the block structure wedge block(Ⅲ)and composite type(Ⅳ).and the countermeasures are put forward according to the main control factors of each type of instability.The slope ratio of the allstrength weathered bedrock is 1∶1~1∶0.75,and theⅠslope should not be too steep,so spray protection should be carried out in time.For typeⅡslope,the anchor(cable)system is used to strengthen and the locking treatment.For typeⅢslope,the unstable block is mainly supported in time.For typeⅣslope,the key instability modes should be found out and corresponding measures should be taken according to geological conditions.According to different geological conditions,different excavation slope ratio and bolt support measures are adopted to ensure the safety of excavation slope and achieve good results.It can provide reference for similar slope engineering investigation,design and construction.
作者
罗飞
贺金明
杨火平
李会中
LUO Fei;HE Jinming;YANG Huoping;LI Huizhong(Three Gorges Geotechnical Consultants Co.,Ltd.,Wuhan,Hubei 430074,China)
出处
《水利与建筑工程学报》
2024年第1期192-197,共6页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金“砂泥岩互层顺倾岸坡地质环境水动力致灾演化机制及预警研究”(U2340226)。
关键词
边坡失稳模式
蠕滑-拉裂型
顺向坡滑移-拉裂型
楔形体剪切-滑移型
复合型
the slope instability mode
creep sliptensile cracking type
slidingtensile cracking type of the dip slope
shearsliding type of the wedge block
composite type
countermeasures
