黄登水电站1号导流洞进口全年围堰拆除爆破

Demolition Blasting of the Inlet Full-time Cofferdam of No. 1 Diversion Tunnel in Huangdeng Hydropower Station

黄登水电站1号导流洞全年围堰受外围条件变化影响整体后移,距离导流洞建筑物进水塔最近处只有50cm,最远处为4m,全年围堰拆除采用分期、分层拆除,最后一次爆破拆除方量超过6000m^3。为保证进水塔安全和确保分流效果,经过多次爆破设计讨论后确定了一次爆破拆除的爆破设计方案,并通过精心造孔、装药、联网施工,最后成功完成拆除爆破,门槽处质点振动速度矢量和未超过设计允许值,并达到很好的分流效果。

The full-time cofferdam of No. 1 diversion tunnel in Huangdeng Hydropower Station moves to tunnel hydraulic structures as the action of peripheral conditions with a minimum distance of 50 cm and a maximum distance of 4 m to intake tower respectively. The cofferdam is dismantled by the mode of staging and layering, and the last blasting demolition volume is more than 6 000 m^3. In order to ensure the safety of intake tower and the diversion effect, the blasting scheme is determined after several design researches. The actual blasting is successful after carefully hole drilling, powder charging and detonation network designing. The monitored vibration velocity vector at gate slot do not exceed design allowable value, and the diversion effect is also better.