软岩区隧洞小净距下穿天燃气管道快速施工技术

Fast Construction Technology of Tunnel Through Natural Gas Pipeline with Small Clear Distance in Soft Rock Area

向家坝灌区一期一步工程邱场分干渠自贡标段王洞隧洞近距离下穿D711城纳线和学堂冲3号隧洞下穿D630泸威线,在提前办理了相关许可证的前提下,先对上部天然气管道进行了保护性施工,到下穿隧洞施工期间通过控制爆破最大装药量达到爆破质点振动速度在允许值范围,以及在50m范围内采用机械开挖的方式,加强了施工期间隧洞的一期支护强度及地表、隧洞的监测力度,隧洞施工安全、快捷的通过天然气管道所涉范围。

Wangdong Tunnel of Qiuchang Sub main Canal Zigong Bid Section of Xiangjiaba Irrigation District Phase I Step I Project underpasses D711 Chengna Line and Xuetangchong No.3 Tunnel underpasses D630 Luwei Line. On the premise of obtaining relevant permits in advance, protective construction was carried out for the upper natural gas pipeline. During the construction of the underpass tunnel, the blasting particle vibration speed is within the allowable range by controlling the maximum blasting charge. Mechanical excavation is adopted within 50m. At the same time, the first stage support strength of the tunnel and the monitoring strength of the surface and tunnel during the construction period have been strengthened, so that the tunnel construction can safely and quickly pass through the scope of the natural gas pipeline.