西藏扎拉水电站主要工程地质问题研究

Study on main engineering geological problems of Xizang Zhala Hydropower Station

西藏扎拉水电站地处青藏高原东构造结,地质条件复杂,为分析其工程建设和运营面临的地质风险,通过工程地质勘察,查明了工程区基本地质条件,论证了主要工程地质问题及影响。结果表明,扎拉水电站主要工程地质问题为:(1)水库坍岸、倾倒岸坡稳定及固体径流问题;(2)坝址坝肩倾倒边坡、近坝卵漂石岸坡、坝基抗滑稳定问题及坝基防渗问题;(3)引水发电系统中引水隧洞受闹中活动断裂影响、引水隧洞及调压室围岩稳定问题、厂房后倾倒边坡稳定问题等。针对以上问题,提出了相应处理措施。研究成果可为工程建设提供科技支撑。

Xizang Zhala Hydropower Station is located in the eastern tectonic junction of the Qinghai-Xizang Plat-eau,the geological conditions are extremely complex.In order to analyze the geological risks of construction and op-eration of the project,through engineering geological investigation,the basic geological conditions of the project area were identified,and the main engineering geological problems and their impacts were demonstrated.The results showed that the geological problems were as follows:reservoir bank collapse,toppling slope and solid runoff problems;②stability of topplingslopeof damabutment at damsite,boulder bank slopenear dampebble,anti-slide and seepage control problem of dam foundation;③influenceofactivefracture,surroundingrock stability problem of diversion tunnel and surge chamber,and stability problem of dumping slope behind powerhouse in diver-sion and power generation system.Moreover,corresponding measures had been proposed to address the above is-sues.The research results can provide a technical support for engineering construction.