A study of influencing factors of negative skin friction by model test

• Main Authors: Kun-cheng Lai, 賴坤成
• Other Authors: 黃俊鴻
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/66318986026573570796

碩士 === 國立中央大學 === 土木工程研究所 === 98 === This research is mainly to simulate behavior of negative skin friction by applying surface loading on the soft soil layer. The type of pile foundation is end bearing pile. By varying different test parameters and loading sequence. The factors influencing negative friction development have been observed. The research put focus on four influencing factors which are the pre-consolidation stress of clay, the area of loading, the order of applied loading and the existence of thin clay layer. Based on the test results, the surface settlement and the negative skin friction of NC clay are greater than those of OC clay. In case of loading of finite area, the neutral plane is more close to ground surface and the negative skin friction is smaller than that of one dimensional loading. The negative skin friction for the case of loading pile first and then applying surface load is larger than the case in a reverse loading order. The existence of thin clay layer above the bearing layer is more easily to develop negative friction and its value is dependent on the strength of soil layer above the thin clay layer.