光面爆破技术在东秀隧道中的应用

Application of Smooth Blasting Technology in Dongxiu Tunnel

光面爆破是一种可控制开挖轮廓面的爆破技术,通过合理的控制爆破的作用范围及方向,可使爆破后的岩面光滑平整,岩面裂隙少,岩壁稳定性增加,从而实现超挖、欠挖和支护的工作量的减少。本文以荔玉高速3标段东秀隧道为例,通过现场调研分析总结隧道开挖时的问题,及多次光面爆破试验,不断优化爆破参数,总结出了适合于该隧道Ⅳ~Ⅴ围岩的爆破方案。经过试验可以看出光面爆破可以有效的控制超欠挖现象,还在一定程度上保持围岩的相对稳定,为隧道施工及经济效益带来一定的成效。

Smooth blasting is a blasting technique for controlled excavation profile.Through the rational controlling of the scope and direction of blasting,the rock surface after blasting has smooth,the phenomenon of rock cracking has been decreased,but the stability of palisades has been enhanced,which achieve the reducing workload in over-break,under-break and support.The paper summarizes the blasting scheme adapting to theⅣandⅤadjoining rock by means of the analysis of problem for field survey when tunnel excavated,multiple smooth blasting test,the constant optimizing of blast index.Results of smooth blasting test show that the blasting scheme can effectively control the over-under-excavated phenomenon,and maintain the relative stability of adjoining rock,which can bring some benefits in tunnel construction and economy.