互层岩体台阶爆破主控岩层的判别方法

互层岩体台阶爆破中力学差异性较大的岩层影响了炸药能量的均匀分布,为了快速确定影响爆破效果的主控岩层的位置及台阶整体炸药单耗,采用数值分析的方式探讨了主控岩层对炸药能量分布特征的影响规律,实验结果表明:采用连续装药结构时力学差异性较大的夹层处质点运动速度更为集中,而间隔装药可改善台阶内速度场的分布均匀程度;由最小抵抗线原理分析发现主控岩层的厚度和力学性质是影响炸药能量传递方向的主要因素;在此基础上结合波阻抗原理,构建了考虑台阶岩体整体力学特性及各岩层局部工程特征的能耗分级体系,通过现场测试取得了良好的应用效果,验证了该方法的可行性,可为互层岩体台阶爆破设计确定合理炸药单耗量和精准设计装药结构提供科学依据。

Distinguishing method of main control stratum in bench blasting of interbed strata

In order to quickly determine the position of the main control stratum and the consumption of explosives in bench blasting, the influence law of the main control stratum on the explosive energy distribution characteristics is discussed by numerical analysis. The experimental results show that when the continuous charge structure is adopted, the particle velocity in the interbed with large mechanical difference is more concentrated, and the interval charge can improve the distribution uniformity of velocity field; based on the principle of minimum resistance line, it is found that the thickness and mechanical properties of the main control stratum are the primary factors affect on the direction of the blasting energy transfer; a classification system of energy consumption is established, which considered the average mechanical properties of all the bench strata and the local engineering characteristics of each rock layer; through the field test, good application results are obtained, and the feasibility of the method is verified, which can provide scientific basis for the reasonable explosive consumption and precise design of charge structure in the design of interbed strata bench blasting.