水下控制爆破辅助冲孔灌注桩成孔施工技术

摘要

If there were hard boulders or rock layers distributed in the formation of pile foundation, it was difficulties to the drilling hole of the pile. Before hole of the pile was drilled, blasting was used in hard rock layer. After hole of the pile was drilled, underwater controlled delay initiation was adopted to assist forming hole of pile; cumulative blasting was used in hard boulders; underwater exposed blasting was used in outshoot stones. Construction efficiency and safety were greatly improved.%桥梁桩基地层中如果分布有坚硬的孤石或者岩石层,给钻孔施工带来极大困难.对于已知坚硬岩石层采取开钻前钻孔爆破(预爆)；对开钻后发现的冲击成孔特别困难的,采用孔内水下延时控制爆破；对于个别岩石块球体采用水下聚能爆破；对探头石采用水下裸露爆破.采取这些措施,使施工工效与安全性大为提高,解决了施工中的难题.