When a coseismic landslide is triggered by an earthquake, seismic stations close to the location of the landslide will simultaneously record the seismic signals caused by the earthquake and landslide, causing confusion between the two signals. This complicates the separation of the two signals, and subsequently the explanation of the coseismic landslide process from the signals recorded. Therefore, the use of a numerical approach is a more practical methodology for systematic analysis of the characteristics of seismic signals generated by the motion of coseismic landslides. In addition, in-depth study of various factors (parameters) that affect the seismic signals of coseismic landslides can be rapidly achieved. This study proposed a dynamic numerical coupling approach, which can simultaneously simulate the earthquake response of the ground and the behavior of the coseismic landslide process as well as trace the seismic signals generated by the two geological phenomena. PFC and FLAC codes were coupled to accomplish the numerical approach. The PFC was to simulate the sliding process of the masses, including rupture and dispersal of the rock masses during movement and collisions as well as the deposition patterns of the masses. The FLAC enabled the input of acceleration history at the base of the FLAC model and the calculation of the propagation of the seismic waves in the strata and the interaction of the seismic disturbances with the PFC model. The Tsaoling coseismic landslide due to the 1999 Chi-Chi earthquake was chosen to serve as an example for the approach, due to the presence of the strong motion station CHY080 in close proximity to the main scarp of the Tsaoling landslide, and its recordings of the seismic signals induced by the coseismic landslide and the Chi-Chi earthquake. The study shows that the numerical evaluation of the energy contribution of the Tsaoling coseismic landslide is approximately 66% of the energy contribution to the seismic signal of the monitoring station in the simulation. A parametric study was also performed on input acceleration, friction of the sliding surface, particle friction, particle bond strength and Rayleigh damping. This study concludes that the major key parameters are normal parallel bond strength, Rayleigh damping and the residual friction of ‘wall elements’ in that they are very sensitive and significantly influence the landslide process and seismic signals of the simulations. The results of the simulations were able to account for most of the physical mechanisms of the coseismic landslides. The coupling approach employed can provide a quantitative basis for evaluating the effects of the parameters on the characteristics of the seismic signals. It can also be extended to assess seismic signals generated from other types of coseismic mass movements.

当地震引发同震滑坡时，靠近滑坡位置的地震台将同时记录由地震和滑坡引起的地震信号，从而引起两个信号之间的混淆。这使两个信号的分离变得复杂，并且随后使记录的信号对同震滑坡过程的解释变得复杂。因此，使用数值方法是对同震滑坡运动产生的地震信号特征进行系统分析的一种更实用的方法。此外，可以快速实现对影响同震滑坡地震信号的各种因素（参数）的深入研究。这项研究提出了一种动态数值耦合方法，它可以同时模拟地面的地震反应和同震滑坡过程的行为，并跟踪由这两种地质现象产生的地震信号。结合PFC和FLAC代码以完成数值方法。PFC用来模拟质量块的滑动过程，包括在运动和碰撞过程中岩体的破裂和扩散以及质量块的沉积方式。FLAC允许在FLAC模型的基础上输入加速度历史记录，并计算地层中地震波的传播以及地震干扰与PFC模型的相互作用。以1999年的Chi-Chi地震造成的Tsaoling同震滑坡为例，由于强地震台站CHY080紧邻草岭滑坡的主要陡坡，并且记录了同震滑坡和集集地震引起的地震信号。研究表明，在模拟中，Tsaoling同震滑坡的能量贡献的数值评估约为能量对监测站地震信号贡献的66％。还对输入加速度，滑动表面的摩擦，颗粒摩擦，颗粒结合强度和瑞利阻尼进行了参数研究。这项研究得出的结论是，主要的关键参数是正常的平行粘结强度，瑞利阻尼和“壁单元”的残余摩擦非常敏感，并且会显着影响滑坡过程和模拟的地震信号。模拟结果能够说明同震滑坡的大多数物理机制。所采用的耦合方法可以为评估参数对地震信号特征的影响提供定量依据。它也可以扩展为评估由其他类型的同震质量运动产生的地震信号。