金沙江某水电站坝址条状山梁卸荷松弛成因分析  

Genetic analysis of unloading relaxation of a strip ridge at a hydropower station dam site on Jinsha River

作　　者：唐晓婷[1] 任光明[1] 韦振新[2] 

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [2]中国电建集团西北勘测设计研究院,陕西西安710065

出　　处：《人民长江》2016年第15期45-49,共5页Yangtze River

基　　金：国家自然科学基金项目(41072229)

摘　　要：金沙江某水电站大坝左坝肩边坡因两条河流切割包围形成条状山梁,岩体卸荷松弛强烈,边坡一定深度范围内呈不同程度张开状,可见张开宽度15 cm。在现场调查资料的基础上,结合地形地貌、地层岩性、结构面发育特征及河谷地应力等因素,综合分析了边坡岩体卸荷松弛的成因。结果表明:金沙江及其支流的切割形成了孤立突出、三面临空的条状山梁,同时边坡垂直高差达350 m,应力释放迅速、强烈;逆向陡倾岩体拉裂、倾倒,并随时间持续剪切错动松弛,最终形成了卸荷深度达112 m的松弛现象。The left abutment slope of a hydropower station on Jinsha River is a strip-type ridge formed by cutting and surrounding of two rivers,and the unloading relaxation of slope rock mass is intense,in a certain depth the rock mass cracked with maxium widest of 15 cm. On the basis of field investigation and combining with the factors such as the landform,stratum lithology,structure development characteristics and river valley ground stress,we carry out comprehensive analysis on the unloading relaxation mechanism. The results show that isolated strip-type ridge with 3 free surfaces is formed by the cutting of Jinsha River and its tributary,and the vertical height of ridge is 350 m. The unloading depth of 112 m is formed by quick and strong stress release,tension fracturing and toppling over of steep and reverse rock mass,and the continuous shearing and dislocation with time.

关 键 词：条状山梁 卸荷松弛 成因机制 金沙江 

分 类 号：P642[天文地球—工程地质学]