西藏直孔水电站深厚覆盖层坝基防渗墙施工

西藏直孔水电站防渗墙(墙体最深达到79 m)建造在青藏高原深覆盖层中,自然条件恶劣,地质条件复杂,给造孔成槽带来极大困难。施工中根据地层的不同特点,分别采用了钻抓法、钻劈法、纯抓法等多种造孔工艺,较好地解决了造孔过程中遇到的各种问题,造孔工效在同类地层中达到较好水平。

Construction Technology for Cut-off Wall in Deep Alluvium of Zhikong Power Station Foundation in Tibet

The cut-off wall(with the maximum wall depth of 79 m) for the Zhikong Hydropower Station in Tibet is constructed in the deep alluvium of Qinghai-Tibet Plateau with poor natural conditions and complex geological conditions,so that it is very difficult to drill a hole for trench.In the construction,many methods such as drilling-clawing,drilling-splitting and pure clawing have been used in the forming of hole,according to the different characteristics of stratum,which solves the various problems encountered in the forming of hole so that its working efficiency is good.