爆炸荷载下岩体破裂影响因素研究

Study on Influencing Factors of Rock Mass Rupture under Explosive Load

为研究岩体在爆炸荷载作用下裂纹扩展的影响因素,采用ANSYS/LS-DYNA动力软件对砂岩爆破裂纹扩展机理进行数值模拟,并考察地应力、自由面和节理等因素对爆破裂纹扩展的影响。结果表明:爆生气体与应力波联合作用下的裂隙区半径是应力波单独作用下裂隙区半径的1.85倍,爆生气体的存在使破岩过程更为有效;当侧压系数不变时,随着初始应力的增加,裂隙区扩展半径减小;自由面产生的反射拉伸应力波导致平行于自由面的裂纹产生;自由面与节理平行或垂直对爆破裂纹的分布有很大影响。

In order to study the influence factors of crack propagation under explosive loading, ANSYS/LS-DYNA dynamic software was used to simulate the crack propagation mechanism of sandstone, and the factors such as ground stress, free surface and joint were investigated.The impact of expansion.The results show that the radius of the fracture zone under the combined action of the explosive gas and the stress wave is 1.85 times of the radius of the fracture zone under the action of the stress wave.The existence of the explosion gas makes the rock breaking process more effective.When the lateral pressure coefficient is constant, With the increase of the initial stress, the radius of the fracture zone decreases, and the reflection tensile stress wave produced by the free surface leads to the crack generated parallel to the free surface.The free surface and the joint parallel or vertical have a great influence on the distribution of the burst.