不同水量下不耦合装药混凝土试件爆破对比分析

为了研究不同水量条件下预裂爆破破坏机理,基于现有的爆破理论,对空气和水不耦合装药爆破进行了理论分析,得出空气和水不耦合装药的孔壁初始压力。在此基础上,应用LS-DNAY(非线性有限元)动力学分析软件,建立三维双孔不耦合装药爆破模型,分析在相同不耦合装药结构条件下,不同水量炮孔孔壁初始压应力;并依据Von Mises破坏准则,分析了炮孔连心线上的有效应力变化过程。在理论和数值模拟的基础上,进行混凝土试件不耦合装药爆破试验。结果表明:在相同的装药条件下,炮孔中水量越少,炮孔壁处产生的初始压力越小,炮孔连心线上的有效应力越小;预裂面平整度越好;同时空气和水混合不耦合装药时,空气部分的预裂面平整度优于含水部分。

Comparison and Analysis of Blasting of Concrete Specimen with Uncoupled Charge under Different Water Yield

In order to study the mechanism of pre-splitting blasting damage under different water yield condition，the theoretical analysis of the uncoupled charge blasting of air and water is carried out based on the existing blasting theory，and it is concluded that the initial hole pressure of uncoupled charge in air and water medium were obtained separately.Based on this，the 3d double holes uncoupling blasting model is established by LS-DNAY（nonlinear finite element） dynamic analysis software.The initial compressive stress of the borehole walls under different water yield was analyzed under the same non-coupling charge structure.According to the Von Mises failure criterion，the effective stress evolution process at the concentric line of blasting hole.The test of uncoupling charge blasting of concrete specimen based on the theory and numerical simulation was carried out.The results showed that under the same charge conditions，the smaller amount of water in blasting hole，the smaller initial pressure at the blast hole wall，the smaller effective stress on the concentric line of the blast hole，and the better flatness the splitting surface.Meanwhile，when the air and water are mixed with uncoupled charge，the flatness of pre-splitting surface of air is better than that of water.