Effect of pore-pressure evolution on the motion of debris flow

• Main Authors: Wan-Ju,Li, 李宛儒
• Other Authors: Meng-Yu,Lin
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/n945by

碩士 === 中原大學 === 土木工程研究所 === 106 === The purpose of this study discusses with the effective of the pore-water pressure evolution on the motion behaviors of debris flow. The pore-water pressure in the soil interacts with the effective stress and shear strength between the particles. The effective stress reduces as the pore-water pressure gradually increases and causes soil liquefy. The initial excess pore pressure generated by the soil liquefaction plays an important role in turning soil layer to debris flow. Therefore, we can consider the initial excess pore water pressure as the threshold condition of debris flow. The relationship between the liquefaction conditions and the diffusion coefficient is constructed in this paper, which can be used as a reference for future soil and rock flow simulation. This research used depth-average momentum equation and one dimensional excess pore pressure diffusion formula to be control formula, which sloved by Fourier transformation method and accomplish a complete excess pore pressure distribution. As the liquefaction condition is fixed made water pore pressure distributed like S sahpe with smaller diffusion coefficient. The distribution of water pore pressure was adding at excess pore pressure slow-dissipating with small diffusion coefficient and made it increased obviously than the hydrostatic pressure did.