黄柏山隧道光面爆破技术

Smooth Blasting Technology of Huangbaishan Tunnel

在围岩条件允许情况下,大断面隧道采用全断面光面爆破技术开挖,可加快施工进度,提高施工效率。而进行全断面开挖时,爆破技术参数的合理性与否将直接决定着隧道爆破的效果。为改善爆破效果,针对赣深高铁黄柏山长大隧道工程地质条件与钻孔机械特点,提出了大断面隧道全断面开挖光面爆破技术方案,并通过工程类比和经验公式计算合理调整了原先的隧道钻爆参数。现场试验结果:隧道开挖断面轮廓较为平整,炸药单耗由试验前1.16 kg/m^(3)降低到1.07 kg/m^(3),炮孔利用率从83.5%提高至91.2%,周边孔孔痕率由试验前的73.6%提高至87.4%,有效地提高了隧道开挖施工进度、降低了施工成本。

With the permission of surrounding rock conditions,adopting the full-face smooth blasting technology can accelerate construction progress and improve construction efficiency in large section tunnel blasting excavation.Meanwhile,the rationality of blasting technical parameters will directly determine the blasting effect of full section excavation.According to the engineering geological conditions and drilling machinery characteristics of Huangbaishan long and large tunnel of Jiangxi-Shenzhen high-speed railway,a full-face smooth blasting technology scheme of large-section tunnel is proposed.Furthermore,the drilling and blasting parameters of tunnel are determined according to the engineering analogy and the empirical formula calculation.Field blasting tests show that the contour of the tunnel excavation section is relatively smooth,the powder factor decreases from 1.16 kg/m 3 to 1.07 kg/m^(3),the utilization rate of blastholes increases from 83.5% to 91.2%,and the peripheral hole mark rate increases from 73.6% to 87.4%,which efficiently improves tunnel excavation process and reduces construction costs.