从工程地质类比的角度看锦屏一级水电站左岸深部裂缝的形成

锦屏一级水电站左岸高陡边坡内部水平向很大深度上发育了大量裂缝。合理解释这一特殊的工程地质现象成为工程地质学的新课题。从工程地质类比的角度对锦屏一级水电站坝区4个边坡工程地质条件进行了详细比较，指出了区域的地壳活动水平和构造应力场强度是普斯罗沟左岸边坡深部裂缝形成的本质原因和前提条件，但是仅仅具备这个条件并不一定在边坡内部出现深部拉裂，普斯罗沟左岸边坡的边坡坡体结构以及岩性组合是深部裂缝形成的物质基础。从力学机制上来讲，它与三滩左岸边坡的变形力学机制应该相同，只是岩性和岸坡结构导致的变形破坏形式不同。

STUDY ON MECHANISM OF DEEP FRACTURES OF JINPING FIRST STAGE HYDROPOWER STATION BY ENGINEERING GEOLOGY ANALOGY

Jinping hydropower station is located at the middle stream of Yalongjiang River and the west side of Jinpingdahewan on the boundary of the Yanyuan County and the Muli Zang autonomous county of Sichuan Province. The deep fractures are well developed at the left abutment slope. By comparing engineering geology conditions of four slopes near the dam area,it is concluded that the regional crustal movement and magnitude of the tectonic stress are the essential causes and prerequisite for deep fractures. The slope structure and rock property provide material foundation for deep fractures. From viewpoint of mechanics,the mechanism of the deep fractures is similar to the deformation mechanism of left slope of Santan,which belongs to typical toppling deformation.