This study investigates wave propagation of layered composite rock mass composed of multiple joints and assorted rock materials. Firstly, the effect of multiple-reflection between joints on wave transmission was explored by modifying the method of characteristics. Secondly, the superposition of direct and indirect transmission induced by multiple-reflection was analyzed. Waveform variations in wave transmission were compared across three different layered composite rock mass. Finally, the effects of wave parameters (frequency), joint parameters (stiffness and number), and rock parameters (wave impedance ratio) on both direct and indirect transmission induced by multiple-reflection were considered. The results indicate that the effect of indirect transmission induced by multiple-reflection on both particle velocity and stress transmission of waves cannot be ignored in many cases. The results further indicate that effect of indirect transmission induced by multiple-reflection on both particle velocity and stress transmission coefficients decreases with increasing incident wave frequency, while it increases with increasing joint numbers. The effect initially increases and subsequently decreases with increasing joint stiffness. Furthermore, the effect of indirect transmission induced by multiple-reflection on the particle velocity transmission coefficient increases while its effect on the stress transmission coefficient decreases with increasing wave impedance ratio.

中文翻译：

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由平行节理和不同岩石材料组成的层状复合岩体中的波传输


本研究研究了由多个节理和各种岩石材料组成的层状复合岩体的波传播。首先，通过修正特征方法探讨了节点间多次反射对波传输的影响。其次，分析了多次反射引起的直接透射和间接透射的叠加。比较了三种不同层状复合岩体的波传输波形变化。最后，考虑了波参数（频率）、节理参数（刚度和数量）和岩石参数（波阻抗比）对多次反射引起的直接和间接传输的影响。结果表明，多次反射引起的间接传输对波的质点速度和应力传输的影响在许多情况下是不可忽视的。结果进一步表明，多重反射引起的间接传输对质点速度和应力传输系数的影响随着入射波频率的增加而减小，而随着接头数量的增加而增加。随着关节刚度的增加，效果最初会增加，随后会减少。此外，随着波阻抗比的增大，多次反射引起的间接传输对质点速度传输系数的影响增大，而对应力传输系数的影响减小。