地铁隧道下台阶爆破参数的优化

On the Optimization of the Blasting Parameters for the Lower Bench Blasting in a Subway Tunnel

以青岛地铁2号线延安路站车站主体Ⅰ部下台阶爆破施工为背景,分析了下台阶前期爆破中存在的问题,对下台阶的爆破循环进尺、炮孔间排距、单孔装药量、单段最大起爆药量、周边眼雷管段别、爆破网络等爆破参数进行了优化。结果表明:优化后的爆破方案,比钻眼个数下降了15.62%,雷管单耗下降了30.5%,单位岩石爆破耗时下降了18.18%,盲炮概率下降了83.33%;使下台阶施工在满足爆破振速的同时,缩短了爆破用时、减少了炸药及雷管单耗,提高了爆破效果。

With the lower bench blasting construction of Section I of the main body of the Yan, an Road Station of Line 2 of Qingdao Metro as a practical example,problems occurring at the earlier stage of the blasting construction for the lower benchare analyzed in the paper, with all the parameters including the blasting-cycle footage hole spacing and row charge for a singlehole,the maximum explosive charge for a single section,detonatorsr segments of the contour hole the blasting network,etc. ,optimized.The results show that the optimized blasting scheme makes the number of drilling holes decrease by 15. 62% ,the consumption of detonators reduce by 30.5 % ,the blasting-taking time for a unit rock decrease by 18.18 % ,and the probability of blind shots drop by 83.33 % ,as a result of all of which the lower bench construction not only meetsthe requirement for the blasting vibration velocity, but also,in the meantime, helps cut down the blasting-taking time, reduce theconsumption of explosive and detonators and improves the blasting efficiency.