小湾水电站高边坡开挖深孔梯段爆破的规模控制

经过对小湾水电站高边坡开挖大规模爆破的有关问题进行的分析，得知多排爆破导致“压死”效应明显，预裂爆破与后部深孔爆破振动叠加，爆破振动加剧。认为预裂爆破时段及其对前排网路可能产生的破坏作用是问题的关键，提出了边坡前最后一次爆破的排数宜控制在7～10排的分区爆破方案及加大预裂孔口堵塞长度的不分区一次爆破方案。

Scale control of deep-hole blasting in benches in high slope excavation for the construction of Xiaowan Hydropower Station

The analysis of the problems concerning large-scale blasting in the construction of the Xiaowan hydropower project indicated that the restricting effects are evident in multi-row blasting, and pre-splitting blasting together with deep-hole blasting has aggravated vibration. The pre-splitting duration and its potential damage to the front row's network are considered the key of the solution. This paper puts forward such a scheme that the number of the rows for the last blasting to be conducted in zones should be controlled to be 7 to 10 rows and the plugging length of the pre-splitting hole should be increased for performing blasting at one go without zoning in slope excavation.