The Influence of Upward Cleft Groundwater on the Stability and the Behavior of Dip Slope Failures

• Main Authors: Cheng-Hsueh Weng, 翁正學
• Other Authors: 林銘郎
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/z9d6k4

碩士 === 國立臺灣大學 === 土木工程學研究所 === 105 === Typhoon Soudelor caused regional landslides in northern Taiwan in 2015. Jhongjhih landslide in district contains a rock–soil interface mixed ground. Groundwater can flow into upper layer through high-angle joints, which would erode the slope and reduce the stability due to upward groundwater. Nevertheless, the effects of upward groundwater on slope stability and the kinematics of dip slope failure caused by groundwater are rarely discussed in the literature. In this research, physical model tests and numerical simulations are used to address these issues under diverse conditions. In the physical model tests use water flow inclinometer is used to observe the effect of upward water. There are three holes at the centerline of water flow inclinometer. The holes allow water to flow from the bottom of inclinometer which can lead to upward seepage. The blocky layer specimen is a board made from gypsum, or composed of artificial diamond shaped rock-like material. The granular layer consists of spherical shaped rock-like material, which is cemented by paste. The three-dimensional distinct element program PFC3D is used to simulate the physical tests. The simulations reduce the value of parameters include element’s friction and bond strength as time goes by. In the simulations, seepage force is applied on the particles under water and water pressure is applied on the block layer. Finally, considering the influences of upward groundwater, this research simulates Jhongjhih landslide to identify the process of this landslide.