三峡工程左岸岸边厂房坝段抗滑稳定研究

三峡工程左岸厂房1~#～5~#机组坝段位于左岸山体缓坡地段,原始地面高程110～140m,坝基开挖高程原定98m,厂房建基面高程最低达22.2m,致使坝下基岩下游边坡开挖形成坡度约54°,临时坡高约70余m的高陡临空边坡.此坝段为缓倾角裂隙相对发育区,建基岩体内有多条倾向下游的长大缓倾角裂隙和少量倾向下游的中倾角裂隙,构成了高陡边坡沿缓(中)倾角结构面的深层滑动稳定问题,对坝基和高陡边坡稳定十分不利.应用不同的计算方法对1~#～5~#机组坝段的抗滑稳定进行计算、校核和验证以确保大坝的稳定安全.

Briefing on Research of Slide and Stability of Dam Section of Units No. 1～5 of TGP''s Left Bank Powerhouse

The dam section of the units No. 1~5 of the left bank powerhouse are located in the slight slope area, the original elevation of which is 110~140m. The elevation planned to be 98m after excavation and the lowest foundation of the powerhouse reaches the elevation of 22. 2 m, so that the excavation of the downstream under the dam forms a high slope of about 54 degree, 70 m high temporarily. Because of many disadvantages geologic activities in the dam site, fissures with slight slope are developed relatively in this dam section. Lots of long and large fissures with slight slope and few with medium slope towards the downstream in the bedrock of the foundation constitute the problems of the deep layer slide and stability by the joints of the high slope. CTGPC has entrusted many domestic units to research the slide and stability of the dam section of units No. 1 - 5 in different methods, check and test to ensure the stability and safety of the dam. Here is concise analysis of the deep slide and stability of the dam section of units No. 1 - 5.