汉江丹江口大坝加高后水库环境地质问题预测

丹江口水利枢纽是综合开发汉江的大型水利工程,坝址位于湖北省丹江口市汉江与支流丹江汇合口下游1.5 km处,分两期开发.初期工程投入运行20多年以来,库坝区地震活动具有水库诱发地震特征.库区除局部库段有崩岸及小规模滑坡活动外,库岸总体是稳定的,且基本不存在浸没问题.后期工程大坝加高后,水库诱发地震仍将存在,但地震活动强度水平和震中位置将不会出现太大变化.正常蓄水位抬高13 m使得水库延长约60 km,同时改变了水库运行现状.库区岸坡变形将集中发生在汉库库尾,将对移民迁建选址有一定影响;库岸再造将主要发生在汉库郧县盆地、李官桥盆地和淅川盆地库段的第四系松散堆积层展布区;局部库段存在的浸没问题需进行工程处理.

Forecast for reservoir geological problems after dam heightening of Danjiangkou hydroproject

Danjiangkou hydroproject is a large-scale hydraulic project for comprehensive development of the Hanjiang river basin,the dam site is located at 1.5 km downstream of the confluence of the Hanjiang river and its tributary of the Danjiang river,and it is constructed in two stages.In more than 20 years after the project was put into operation,the earthquake activities in the dam site and the reservoir area possess feature of induced earthquake by the reservoir.The reservoir bank is stable in general,except local land collapse and small scale landslide,and basically there isn't immersion problem.After the dam heightening,the induced earthquake by the reservoir will still occur,but earthquake activities and earthquake centre will not change greatly.The 13 m rise of the normal impoundment water level will extend the reservoir about 60 km,and change operation status quo of the reservoir.The bank slope deformation will occur mainly at the head area of the Hanjiang reservoir,and has some influence on resettlement site selection for relocates;the reservoir bank reformation will occur in loose accumulative horizon of Quaternary in Yunxian basin,Liguanqiao basin and Xichuan basin.The engineering treatment measures should be taken for local immersed reservoir bank.