爆破应力波中远区破岩作用分析

Rock Breaking Effect of Blasting Stress Wave at Moderate or Far Distance

应用断裂与损伤力学理论,分析了爆破应力波远区破岩作用机理认为爆破应力波在远区的破坏效应是基于该区域内局部岩体强度和断裂韧度降低,使衰减后的弱应力波作用强度仍可能大于该点处的岩石极限强度所致。提出岩石损伤与缺陷的存在,会产生应力集中或放大效应的依据,并阐述爆破应力波作用下远区原生裂纹扩展的理论分析,给出了基于岩石损伤的裂纹扩展长度估算模型。

By applying fracture and damage mechanics,the rock breaking mechanism of blasting stress wave at distant place is analyzed.It is held that the breaking effect comes from the reduction of strength and breaking toughness of local rock at distant place,dut to which the strength of attenuated weak stress wave is still greater than the ultimate strength of rock body at one point.It is proposed.that rock damage and defect will result in stress concentration or amplification. The theory on primary crack extension at distant place of blasting stress wave has been elaborated,and the model for estimating the crack propagation length which is based on rock damage has been presented.