光面爆破技术在浅埋大断面隧道掘进中的研究与应用

Study and Application of Smooth Blasting Technology in Piercing Shallow Tunnel with Large Cross Section

昆沪高速黄连山隧道为浅埋、超大断面的高铁双线隧道,地质围岩条件复杂,整体稳定性较差,工程质量要求高。从爆破效果与施工安全角度出发,采用理论分析、现场试验的方法对黄连山隧道的光面爆破进行了系统研究,得出了一套较好的爆破方案,特别对周边孔的爆破参数作出了详细地分析与优化,最终使得炮孔利用率为95%左右,平均超挖量控制在6～10cm,半孔率为75%左右,隧道的开挖质量全部达到了铁路隧道的质量和安全要求。研究结果对类似环境条件下的浅埋大断面隧道掘进具有一定的借鉴意义。

The tunnel of Huanglianshan mountain of Shanghai-Kunming high-speed railway involves the shallow double-track tunnel of high-speed railway with oversized cross section,with complicated surrounding rock in geologic conditions,poor integral stability and high requirement to engineering quality.One set of better blasting scheme was acquired through systematic study of the smooth blasting of the tunnel of Huanglianshan Mountain by using the method of theoretical analysis and field test from the aspects of blasting effect and construction safety;especially,the hole utilization ratio was about 95%,the average volume of overbreak was controlled within 6～10cm,the semi hole ratio was controlled at about 75%,and the excavation quality of the tunnel achieved the quality and safety requirements of the railway tunnel completely after detailed analysis and optimization of the blasting parameters for the peripheral hole.Moreover,the research result has certain significance of reference for piercing shallow tunnel with large cross section under the similar environmental condition.