三江口水电站1号滑坡体成因机制及稳定性分析

Cause and Stability Analysis of the No.1 Landslide Mass of Sanjiangkou Hydropower Project

阿墨江三江口水电站坝前右岸发育一规模较大的1号古滑坡体。依据野外勘察、试验成果,从定性与定量两个方面对滑坡体的稳定性进行分析、计算,1号滑坡体在天然状态下处于稳定状态,水库畜水后,在正常蓄水及各种不利工况条件下,滑坡体总体仍基本处于稳定状态。三江口水电站已于2010年7月下闸蓄水,2010年9月3台机组全部投产发电。变形监测结果表明,1号滑坡总体位移量并不大,且主要集中在2010年,2011年以来已趋于稳定,鉴于滑坡体距枢纽区大坝较近,仍应重视监测、预警,加强巡视、观察,消除人为活动对滑坡的不利影响,加强库水位的运行控制,避免水位骤降或暴涨暴落。

The No. 1 ancient landslide body, large in size, develops upstream of the dam at the right bank of Sanjiangkou Hydropower Project located on the Amojiang River. According to the field investigation and the test results the landslide body stability was analyzed and calculated both qualitatively and quantita- tively. The No. 1 landslide body is stable under a natural state and is still basically stable at the normal storage level and under various unfavorable operation conditions as a whole. The gate closure and impoun- ding of Sanjiangkou Hydropower Plant took place in late July, 2010 and all of the 3 generating units were put into commercial operation in September, 2010. The deformation monitoring results reveal that the to- tal displacement of the landslide body is not large, which mostly appeared in 2010 and tends to be stable since 2011. In view of the landslide body being close to the dam, great importance shall still be attached to monitoring and early warning, inspection and observation shall be enhanced, adverse influence caused by artificial activities shall be eliminated on the landslide, and the control of reservoir level operation shall be strengthened to avoid drawdown or sharp rise and sharp drawdown of water level.