空孔对爆生裂纹扩展的力学行为研究  

Study on the Mechanical Behavior of Empty Holes on Blasting Crack Propagation

作　　者：梁瑞[1] 王兵兵 周文海 侯家宝 祁芳霞 LIANG Rui;WANG Bingbing;ZHOU Wenhai;HOU Jiabao;QI Fangxia(School of Petrochemical Technology,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学石油化工学院,兰州730050

出　　处：《有色金属工程》2023年第11期82-88,125,共8页Nonferrous Metals Engineering

基　　金：国家自然科学基金资助项目(11901264);甘肃省青年科技基金(22JR5RA303)。

摘　　要：为了探究空孔对爆生裂纹扩展的影响,结合ANSYS/LS-DYNA有限元软件建立了空孔爆破损伤模型,理论上推导了空孔附近的岩体质点应力分布方程,分析了空孔效应对于破碎机理与裂纹扩展的影响。结果表明:空孔自由面效应会在空孔附近引起冲击压力骤增和震速变化,出现迎爆面处岩石“片落”现象;空孔背爆面处的震速明显小于迎爆面的震速,说明空孔具有很好的泄压降震效果;通过对冲击压力和裂隙区半径的解析解计算与数值计算结果对比,冲击压力的误差11.81%,而裂隙区半径的误差9.49%,两者结果较为接近。In order to explore the influence of empty hole on the propagation of blasting cracks,an empty hole blasting damage model is established by combining ANSYS/LS-DYNA finite element software.The equation of stress distribution in the rock mass near the empty hole is deduced theoretically,and the influence of empty hole effect on the fracture mechanism and crack propagation is analyzed.The results show that the free surface effect of empty hole will cause the sudden increase of impact pressure and the change of seismic velocity near the empty hole,which leads to the phenomenon of"falling"of rock at the blasting surface.The shock velocity at the back surface of the empty hole is significantly smaller than that at the front surface,which indicates that the empty hole has a good effect of pressure relief and shock reduction.By comparing the analytical solution of the impact pressure and the radius of the fracture zone with the numerical calculation results,it is found that the error rate of the impact pressure is 11.81%,and the error of the radius of the fracture zone is only 9.49%,which proves the accuracy of the simulation results in this paper.

关 键 词：空孔效应 数值模拟 应力集中 裂纹扩展 

分 类 号：TD235[矿业工程—矿井建设]