JMC对应力波透射系数和节理比刚度影响的实验研究

 节理对岩体的动态力学特性有重要影响。采用改进型霍普金森花岗岩压杆(SHPB)实验设备，研究一维应力波在花岗岩人工节理处的传播规律，进而分析节理的动力学特性。通过切割工艺在花岗岩试样表面形成人工节理，使其具有不同的节理吻合系数(JMC)。采用两点式波分离方法处理实验数据，得到节理处的入射波，以及节理产生的反射波和透射波，进一步计算得到应力波传播通过节理的透射系数。基于SHPB实验的基本原理，得到节理的闭合量和作用在节理上的压力之间的关系，从而分析出节理的比刚度。该实验分析节理吻合系数对波传播的影响，进而研究节理吻合系数对花岗岩节理动态力学特性的影响。

Experimental research of JMC effect on stress wave propagation and joint specific stiffness

Joints have significant influence on the dynamic properties of rock masses. Using the apparatus of modified split Hopkinson pressure bar(SHPB)，an experimental study was carried out on one dimensional stress wave propagating through the artificial granite joint. The interfaces of granite specimens were sawn to form the artificial joints with different joint match coefficients(JMCs). The incident wave across the joint and the reflected wave and transmitted wave induced by the joint were obtained with the method of two-points wave separation and then the transmission coefficients of the stress wave propagation through the joints were calculated. The relation between the pressure and closure of the joint was obtained according to the principles of SHPB test，thereby the specific stiffness of the joint was acquired. The effects of the joint match coefficients on wave propagation through the joint and on the dynamic mechanical behavior of the granite joint were discussed.