岩块断裂对块系岩体摆型波传播影响试验

Experimental on the effect of block fracture on pendulum-type wave propagation in block-rock mass

摆型波是块系岩体中的一种非线性动力传播现象,为研究块系岩体中局部岩块断裂时的摆型波传播规律,采用试验方法研究了岩块的断裂方向和断裂位置对摆型波传播的影响,分别从摆型波的传播速度、岩块加速度、动能、位移响应及加速度频域响应特性等方面进行分析.结果表明:当岩块发生断裂时摆型波在块系岩体中的传播速度下降,岩块振动持续时间延长,岩块加速度和动能最值均出现下降,加速度信号中心频率下降,岩块位移的最大值出现增大;同时得出,岩块纵向断裂和在近冲击源位置断裂这2个因素对摆型波传播过程岩体动力响应特征的影响更大.该研究将为块系岩体存在局部岩块断裂时摆型波传播特征识别及岩体的断裂预警提供参考.

The phenomenon of pendulum-type wave is a nonlinear dynamic propagation in block rock mass. The influence of local block fracture direction and fracture position to pendulum-type wave propagation is studied by experiments. In this paper,the propagation velocity of pendulum-type wave,block rock acceleration,kinetic energy,displacement response and acceleration frequency domain response characteristics of rock blocks are analyzed respectively. The results show that when the rock block fractured,the propagation velocity of pendulum-type wave in block rock mass decreased,the vibration duration of rock block prolonged,the maximum acceleration and kinetic energy of rock block decreased,the frequency domain center of the acceleration signal decreased,and the maximum displacement of rock block increased. At the same time,the longitudinal direction fracture of rock block and the fracture position near the impact source have greater influence on the dynamic response of rock mass during the propagation of pendulum-type wave. This study provides a reference for identifying the propagation characteristics of pendulum-type wave when block fractured and warning rock fracture.