摘要
采用微差控制爆破与分步开挖相结合的施工方法。第一步 ,用垂直孔和楔形掏槽开挖沉井中央的基岩 ,用三个凿岩爆破循环开挖到设计标高 ,形成一个直径 4 1m、深 3 4m井。第二步 ,用水平孔开挖厚 0 6 5m井壁 ,每循环下挖 0 5m ,即沉井每次下沉 0 5m ,直至下沉到位。文中主要介绍了炮孔布置、爆破参数选取和起爆顺序设计。
A construction method of combining short-delay controlled blasting with stepped excavation was adopted.Firstly,the vertical blastholes and wedge-shaped cut were used for excavation of base rock in the centre of the well foundation,and a well with a diameter of 4.1 meters and depth of 3.4 meters was formed with three rounds.Secondly,the horizontal holes were used to excavate the well wall with a thickness of 0.65 meters,with a excavating depth of 0.5 meters per round.In other words,the well foundation fell down by 0.5 meters per round until reaching the predetermined position.The blasthole pattern,blasting parameter selection and firing sequence design were mainly presented in this paper.
出处
《工程爆破》
2002年第2期42-44,共3页
Engineering Blasting
关键词
微差控制爆破
分步开挖
凿岩爆破
爆破参数
桥梁
沉井
Base-rock excavation
Well foundation
Short-delay controlled blasting
Stepped excavation
