Study on Lateral Spread Affected Piles Using Direct Earth Pressure Model and Wave Equation Analysis

• Main Authors: Kai-Feng Liu, 劉凱方
• Other Authors: Der-Wen Chang
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/96827196569734788607

碩士 === 淡江大學 === 土木工程學系碩士班 === 97 === This study following the methodology suggested by JRA, is to study the single pile dynamic behavior under lateral spreading of soil. It applies the programming language of Fortran to exploit the analysis. Liquefaction potential analysis in this study is Tokimatsu and Yoshimi method, which applies by Microsoft Excel. The research result is essentially founded on the model of wave equation analysis, and the difference equations are used to solve the problem. The stiffness of piles are started iterative analysis by using simplified Bouc-Wen model. This study aims to examine the deformation and destruction of the pile foundation. Three research results are derived in this conclusion: First, this study suggests adopting Ishihara’s theory of lateral earth pressure, in replace of the traditional fixed head, into consideration in order to the flexibility of non-liquefiable and base layer. Second, the data of the liquefaction potential index and the depth of liquefiable layer by calculating can be gathered by Liquefaction potential analysis. The liquefaction potential index is one of the JRA method parameters, and it can influence the earth pressure of the layer which is upon the liquefiable layer very much. The result of this study proves that the depth of liquefiable layer influences the behavior of pile foundation a lot. Third, the head of pile in this study is fixed head. The max displacement of pile occurs on the head of pile foundation. The larger value of the bending moment of pile occurs on the head of pile foundation or near the base of the liquefiable layer. According to the result of this study, the layer liquefies and make the soil flow when the earthquake is happened. The result of this study make us know well that the displacement and the deformation of pile foundation, and can consider that the destruction owing to the bending moment of pile foundation which is near the base of the liquefiable layer.