预裂爆破技术在呼和浩特抽水蓄能电站中的应用

Application of Presplit Blasting in the Construction of Hohhot Pumped-storage Power Station

呼和浩特抽水蓄能电站拦沙坝建基面开挖采用预裂控制爆破技术,通过搭设钻机作业的钢管架,采用间隔不耦合装药结构,严格控制钻孔方向、倾角和单孔装药量,避免了建基面出现欠挖和超挖量过大现象,预裂缝的形成降低了爆破震动影响,基岩无爆破裂隙出现,开挖质量优良。

The excavation of dam-foundation interface for the river dam in Hohhot Pumped-storage Power Station is conducted by using presplit blasting technology. By erecting steel frames for holes drilling, adopting uncoupling charging structure with interval and strictly controlling drilling direction and inclination and unit charge volume, the excessive overand under-excavations are avoided. The pre-craeks also reduce the impact of blasting on bedrock and there is on crack in bedrock caused by blasting. The practice shows that the excavation quality is excellent.