富水断层影响带引水隧洞预埋式岩塞爆破技术

摘要

The ancient water diversion tunnel, belong to the integrated management engineering of Wangkuai and Xidayang Reservoir, is located in the fault zone. The surrounding rock is broken and contains rich groundwater. Hydraulic fissure water is closely related to surface water. Making full use of the emptying reservoir, artificial embedded concrete plug retaining water was casted, before the formal program. Using cement and sodium silicate grout, advance grouting was completed before the rock plug blasting. Some problems, such as cavity pours water and surrounding rock crushing, were solved successfully, which provided favorable conditions for later rock plug blasting. Based on this, by adopting double network, millisecond delay detonator, peripheral hole no using pre-splitting blasting, rock ballast treatment without slag collecting pit or buffer pit, the plug blasting was very successful. Practice has proved that embedded rock plug scheme is feasible, and the key to smooth blasting of rock plug and diversion tunnel digging is advance grouting and reasonable blasting scheme.%保定市王快—西大洋水库综合管理工程渠首引水隧洞位于断层影响带，围岩破碎且富含地下水，裂隙水与地表水水力联系密切。工程实施时充分利用水库放空时机，在引水隧洞取水口采用现浇混凝土形成人工预埋式挡水岩塞；岩塞爆破前采用水泥和水玻璃浆液进行了超前预注浆，成功解决了洞室涌水、围岩破碎等问题，为后期岩塞爆破提供了有利条件。在此基础上，采用毫秒延时起爆双网路、排孔爆破、周边未预裂爆破，取得了理想的爆破效果。实践证明，预埋式岩塞方案可行，超前预注浆及合理的爆破方案是确保引水隧洞掘进及岩塞顺利爆破的关键。