爆破载荷作用下围岩裂隙发展特征试验研究

为研究爆破载荷条件下围岩损伤范围与裂隙扩展行为问题,以云南红河州咪的隧道爆破开挖为背景,通过理论分析与室内模型试验分析方法,以Froude比例法建立爆破载荷作用下裂隙发展试验模型,分析爆破载荷作用下围岩试样的动态力学与裂隙发展趋势.结果表明:通过对空气间隔装药孔壁压力计算得到应力波作用下裂隙范围计算公式,同时基于爆生气...

Experimental on Development Characteristics of Surrounding Rock Fissures Under Blasting Load

In order to study the damage range and crack propagation behavior of surrounding rock under blasting load, the blasting excavation of tunnel in Honghe Prefecture, Yunnan province is taken as the background. By means of theoretical analysis and laboratory model test, a test model of fracture development under blasting loading was established by Using Froude proportion method, and the dynamic mechanics and fracture development trend of surrounding rock samples under blasting loading were analyzed. The results show that :(1) The calculation formula of fracture range under the action of stress wave was obtained by calculating the pressure of the hole wall of the air interval charge. Meanwhile, based on the secondary expansion of the explosive gas entering the explosive fracture, the calculation formula of the damage range of surrounding rock under the action of blasting load was obtained; (2) The blasting shock wave exerts compression and tension on the model, and the crack is mainly affected by the joint action of compression wave and unloading wave. The crack mainly develops along the direction of the hole and is perpendicular to the axis of the hole. (3) The expansion of blasting fissure can be controlled by proper spacing of holes, which has a guiding effect on the development of blasting fissure.