Combined Hydrology and Slope Stability

by Craig Abram Jordan, M.S. Washington State University Chair: Balasingam Muhunthan Landslides constitute a major geological hazard in the world due to their high financial cost and their nondiscriminatory nature. The Olympic Region of Washington State has many potential triggers of landslides, but prolonged periods of high rainfall is the most commonly attributed trigger of landslides. The current state of practice for landslide prediction is to assume pore water pressure above the phreatic surface is negligible; this methodology is incapable of accurately forecasting shallow landslides where suction plays a critical role. Suction varies with moisture content and as such a hydrological model that can be prescribed with varying vegetation and climate realizations should be used along with a stability model that includes soil suction to better predict shallow landslides. This study presents a methodology to predict the stability of shallow planar slope failures that incorporates the hydrologic modeling capabilities of the program