深基坑开挖钻爆施工技术

Construction Techniques of Drilling and Blasting for the Excavation of Deep Foundation Pits

以青岛地铁建设为工程背景,对深基坑开挖钻爆施工技术进行了分析研究。针对首段爆破段没有侧向临空面、不易爆破的特点,提出采用掏槽沟开挖爆破法,形成侧向临空面,确保了后续爆破的成功进行。车站主体开挖采用浅孔台阶预裂爆破技术,提高了施工效率,较好的保护了前期支护结构,取得良好的爆破效果。

With the project of the Qingdao Subway as the engineering background,the techniques of drilling and blasting for deep foundation pits are analyzed and studied in the paper.With the characteristics of there being no free surface in the first section to be blasted and therefore the first section being difficult to blast considered,the method of ditch-cutting and blasting is put forward.Owing to the application of the method,the side free surface is formed,after which the following blasting processes can be performed successfully.The excavation for the main body of the subway station adopts the techniques of short-hole-bench-and-pre-spliiting blasting,which improve the construction efficiency,help protect the pre-support structure and achieve very good blasting effect.