精细爆破在地铁硬岩深基坑开挖中的应用探究

Application of Fine Blasting in Excavation of Hard Rock Deep Foundation Pit in Subway

结合工程实例,介绍了精细爆破在地铁硬岩深基坑开挖中的具体应用。为充分满足复杂地质环境的要求,根据现场工程地质条件,在硬岩基坑开挖中采用了"中部拉槽、横向分区、纵向分段、竖向分层"的精细爆破开挖方案,增加了爆破自由面。同时,结合理论实践和现有技术经验,从开槽爆破、松动爆破和光面爆破、炸药的选用和装药结构、起爆网络、岩石爆破安全校核等多方面分析了精细爆破在地铁硬岩深基坑开挖中的具体应用,以期加快施工进度,提升精细爆破开挖施工的安全性。

Combined with the engineering project,this paper introduces the application of fine blasting in deep excavation of hard rock in subway. According to the site engineering geological conditions,in order to fully meet the requirements of the complex surrounding geological environment,in the excavation of hard rock foundation pit,a fine blasting excavation scheme is adopted,which is central drawing trough,lateral zoning,longitudinal section and vertical stratification,and it increases the free surface of blasting. Based on the combination of the theory and practice and the existing technical experience,the application of fine blasting in the excavation of the deep foundation pit of the subway is analyzed from such aspects as the slotting blasting,the loose blasting and the smooth blasting,the selection of explosives and the charge structure,the detonation network and the rock blasting safety check,hoping that the safety of the construction of the fine blasting excavation can be improved and it helps to speed up the construction progress.