Feasibility Study on Using Numerical Manifold Method Integrating Discontinuous Deformation Analysis to Simulate the Landslide Induced Signals

• Main Authors: Chi-HsienWu, 吳奇弦
• Other Authors: Der-Her Lee
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/k34e8d

碩士 === 國立成功大學 === 土木工程學系 === 107 === Landslide induced signals are thought to be related to the process or mechanism of landslide events. This study aims to verify the feasibility of using a discontinuous numerical method to simulate landslide induced signals and also connect the relationship between landslide movement behavior and signals. This study simulates the Xinmo landslide induced signal by using a two-dimensional numerical manifold method integrating discontinuous deformation analysis (NMM-DDA). This study also utilizes fast Fourier transform (FFT) and short-time Fourier transform (STFT) to explore the characteristic of signals in the frequency domain. This study revises boundary conditions and meshes size of NMM elements to improve the accuracy of simulated signals. Two mesh sizes are conducted, coarse mesh and fine mesh respectively. The simulation result shows that NMM-DDA can not only demonstrate the process of Xinmo landslide well but also produce the near-site signals. Through a characteristic comparison of MXI station signal and simulated signals, this study suggests that it is feasible to simulate the landslide induced signal by using NMM-DDA. The coarse-mesh model signal appears to be the status after long-distance wave propagation. Besides, the fine-mesh model signal has more high-frequency content in the STFT spectrum. The relationship between landslide movement behavior and signals has been discussed through spectral analysis. The result shows that collision behavior can create more high-frequency content and velocity amplitude than sliding behavior.