重庆鲤刘区间地铁隧道浅埋硬岩爆破开挖方案优化

Optimization of Blasting Scheme of Excavating for Shallow-buried Subway Tunnel in Hard Rock

重庆地区地铁九号线鲤-刘区间属于浅埋隧道,穿越围岩以硬岩为主,施工效率低,对围岩和周围构筑物影响较大。为此优选了钻爆参数,计算了安全药量和单孔装药量,基于错相减震机理选择起爆方式、炮孔布置参数及起爆顺序。现场应用结果表明,采用爆破新工艺参数后,比原工艺单孔单响爆破时振动降低了58%。

The Li-Liu section of the No. 9 subway line in Chongqing is a shallow buried tunnel. The surrounding rock is mainly composed of hard rock, with low construction efficiency and great influence on surrounding rock and sur- rounding structures. For this reason, the drilling and blasting parameters were optimized, the safety dose and the sin- gle-hole charge were calculated, and the detonation mode, the blast hole arrangement parameters and the detonation sequence were selected based on the phase-shifting mechanism. The field application results showed that after using the new blasting process parameters, the vibration was reduced by 58% compared with the original single-hole sin- gle-shot blasting.