沉井内钻孔定向爆破助沉就位技术简介

A BRIEF ACCOUNT OF THE ORIENTED EXPLOSION HELPING SINKING AND POSITIONING TECHNIQUE OF BOREHOLE WITHIN A OPEN CAISSON

目前,国内大型桥梁施工中,深水中沉井基础下沉就位嵌岩往往靠潜水员水下爆破作业,效率低,进度慢。有时还会造成潜水员的伤亡和沉井的歪斜。本文介绍了在沉井上部搭台架设钻机,进行水下钻孔,孔内分层定向爆破技术。该技术可使沉井下沉就位快,嵌岩准确,收到明显的经济效益。

At preseut, for large bridge construction in our country, the caisson foundation sinking, positioning, and rock inlay are usually done with underwater explosion by the diver of low efficiency and slow progress.sometimes it may cause the divers casualty or the slanting of caisson. This paper introduces a technique of erecting framework and rig at the upper part of the caisson, making underwater boring and oriented explosion by layers within the bore hole.This technique can make quick sinking, positioning and precise rock inlay of the caisson. The economic benefit is obvious.