An Investigation of some Factors that Triggered Landslides

• Main Authors: Chih-Yen Li, 李芷妍
• Other Authors: Min-Hua Wei
• Format: Others
• Language: en_US
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/s8n6xv

碩士 === 國立臺北科技大學 === 土木與防災研究所 === 95 === The geology of Taiwan is complicated, and the precipitation is rich and concentrated. Three quarter of Taiwan is made up of hillsides and the increase of the island population has directed many new developments towards the hillsides. As a result, the number of slopes failure has also increased; this is particularly so after a heavy rainfall for residual soil slopes. In mostly cases, due to the unique location of ground water table in the slope, soils between the slope surface and ground water table are in unsaturated state. It’s called unsaturated soil. During long raining season, heavy rainfall intensity will inevitably force the shear strength of these soils to depreciate and subsequently cause the slope to fail. Consider the engineering characteristics such as matric suction of unsaturated soil in the stability problem. In this study, four typhoons: Haitang, Matsa, Talim and Longwang have been found to cause 1718 slope failures in 2005. Based on the forensic diagnosis of the observed failures, we can generalize the important factors for slope failures. Numerical analysis using SoilVision program is adopted to model the NTUA slope failure. Uncertainties such as soil layer distribution, ground water table, rainfall distribution and laboratory testing may affect the result of the stability analysis of slope. Finally, this study assessed the effect and contribution of soil parameters to an unsaturated slope.