三峡右岸地下电站引水隧洞开挖控制爆破技术研究

The study on controlled blasting in excavation of diversion tunnels of the underground power plant on the right bank of Three Gorges project

三峡右岸上游大坝帷幕作为防止地下渗漏的一道屏障,对于三峡水库的作用极其重要,在地下电站引水隧洞开挖爆破施工过程中,保证这道屏障不出现裂缝,确保不形成渗水通道,也是一个极其复杂的难题。地下电站引水隧洞爆破开挖与三峡工程上游大坝帷幕最小距离为3.78m,爆破难度高,为此,针对不同部位,探讨了多分序、控制爆破最大单段药量、预设爆破隔震带和爆破隔震孔等多种控制措施,以确保上游大坝帷幕安全。

The right bank upstream grout curtain under the dam of the Three Gorges project, as a seepage control measure, is very important to the Three Gorges reservoir. It is also a very complex problem of how to protect this grout curtain from damage and seepage during blasting operation of the diversion tunnels of the underground power house, The blasting site of the diversion tunnels for the underground power house was only 3.78 m in distance （minimum） from right bank upstream grout curtain under the dam of the Three Gorges project. So in order to protect the upstream grout curtains of the dam, a few ahematives for different localities have been discussed , including muhi-sequence, controlled maximum charge of explosives, pre-arranged isolation zone and vibration isolation holes.