竖井中导井一次爆破成井法的研究与应用

Research and application of the one shot blasting pilot hole sinking method for the shaft

摘要:

本文以某水利工程闸门井竖井开挖为例，中导井开挖尺寸2 m×2 m，通过实践总结研究，介绍了竖井中导井施工开挖的一种新方法——中导井一次爆破成井法，着重介绍了中导井如何一次爆破贯通的技术措施。本工法采用中导井一次爆破成井和竖井周边扩挖相结合。开挖方法采用深孔爆破法，通过爆破方案设计、施工前准备、机械钻孔、装药、联线、爆破、炮后安全检查等工艺，先对中导井进行一次爆破开挖成型，再对竖井周边岩体自上而下采用浅孔多循环爆破扩挖成型，最终形成竖井中导井。

Abstract:

In relation to the gate shaft excavation at a water conservancy project where the excavation size is 2 m×2 m for the shaft pilot hole， this paper introduces a new excavation method-the one shot blasting method for sinking of the central pilot hole with emphasis on the technical measures on how to complete the central pilot hole by one-time blasting. With this method， one shot blasting for the central pilot hole is combined with expanding excavation around the hole. The deep hole blasting method is adopted for excavation. Through the design of the blasting scheme， preparation before construction， mechanical drilling， charging， wire connection， blasting， safety inspection after blasting and other processes， the central pilot hole is first excavated and shaped by one shot blasting， and then it is expanded and shaped by shallow hole multi-cycle blasting through the surrounding rock from top to bottom， and finally the central pilot hole is formed.