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(1 同濟(jì)大學(xué)地下建筑與工程系，上海 200092； 2 同濟(jì)大學(xué)巖土及地下工程教育部重點(diǎn)試驗(yàn)室，上海 200092； 3 福建省交通規(guī)劃設(shè)計(jì)院，福州 350004)
［摘要］采用室內(nèi)模型試驗(yàn)與顆粒流(PFC-2D)數(shù)值模擬相結(jié)合的方法，對(duì)被動(dòng)樁在砂土中土拱形成機(jī)理進(jìn)行了較系統(tǒng)和深入的研究。研究表明，拱效應(yīng)是多種因素的組合；樁間距、砂土顆?？紫堵屎蜆锻两佑|特征對(duì)土拱效應(yīng)的影響最明顯；樁間距小、孔隙率小、樁土接觸面粗糙或密實(shí)度大的土體，易形成土拱；土拱并不是一成不變的，隨著顆粒排列調(diào)整，可能在此過(guò)程中破壞或重新形成。
［關(guān)鍵詞］土拱效應(yīng)；被動(dòng)樁；模型試驗(yàn)；影響因素；細(xì)觀(guān)；樁土接觸特征
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
國(guó)家自然科學(xué)基金資助項(xiàng)目(50578122)。
作者簡(jiǎn)介：周健，博士，教授，博士生導(dǎo)師，Email:tjuzj@vip.163.com。
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