(1 同济大学地下建筑与工程系，上海 200092； 2 同济大学岩土及地下工程教育部重点试验室，上海 200092； 3 福建省交通规划设计院，福州 350004)
［摘要］采用室内模型试验与颗粒流(PFC-2D)数值模拟相结合的方法，对被动桩在砂土中土拱形成机理进行了较系统和深入的研究。研究表明，拱效应是多种因素的组合；桩间距、砂土颗粒孔隙率和桩土接触特征对土拱效应的影响最明显；桩间距小、孔隙率小、桩土接触面粗糙或密实度大的土体，易形成土拱；土拱并不是一成不变的，随着颗粒排列调整，可能在此过程中破坏或重新形成。
［关键词］土拱效应；被动桩；模型试验；影响因素；细观；桩土接触特征
Meso-mechanism analysis on soil arching and effect factors surrounding passive laterally loaded piles
Zhou Jian1,2, Qi Bin1,2, Zeng Qingyou3(1 Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China; 2 Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education,Tongji University,Shanghai 200092,China;
 3 Fujian Communication Planning & Design Institute, Fuzhou 350004, China)Abstract:It applies model tests and PFC-2D (Particle Flow Code in Two Dimensions) numerical simulation method to perform a systematical and deep research in the mechanism and behavior of soil arching surrounding passive piles in sand. The results indicate that pile spacing, porosity of sand and interface conditions play very important roles in soil arching effects. The arching effects are many kinds of factors- combination. The small pile spacing, fine porosity, worse interface condition or compact sand are easy to form soil arching. The soil arching is not constant, and due to arrangement of particles, arching maybe failed or reformed.
Keywords:soil arching effect; passive laterally loaded pile; model test; effect factors; mesomechanism; interface conditions between pile and soil
国家自然科学基金资助项目(50578122)。
作者简介：周健，博士，教授，博士生导师，Email:tjuzj@vip.163.com。
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