桩承式路堤土拱效应的试验和数值研究  

Experimental and numerical studies of soil arching in piled embankment

作　　者：费康[1,2] 王军军[2] 陈毅[2] 

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,南京210098 [2]扬州大学岩土工程研究所,江苏扬州225009

出　　处：《岩土力学》2011年第7期1975-1983,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.50908198);江苏省高校自然科学研究基金(No.09KJB580004);河海大学岩土力学与堤坝工程教育部实验室开放基金(No.GH200805)

摘　　要：对桩承式路堤中的土拱效应进行了三维模型试验研究。根据试验结果,分析了应力折减系数大小和填土中的竖向应力分布特点。对比分析了实测值与Terzaghi方法和Hewlett&Randolph方法计算值之间的差异,验证了各方法的适用性。采用三维有限元对模型试验进行了数值模拟,重点分析了路堤填土的大主应力方向、应力水平和沉降模式等几个关键问题。试验和数值结果表明,Terzaghi方法与Hewlett、Randolph方法给出的应力折减系数数值接近,但填土中竖向应力分布模式截然不同,且与实测值有所区别。若在Terzaghi方法中采用合适的滑动面形状,得到的计算结果与实测值较吻合,能够反映竖向应力沿深度分布的特点。In order to improve the understanding of soil arching effect in the piled embankment, a series of three-dimensional model tests were carried out. The stress reduction ratio and the vertical stress distribution in the embankment fill were studied in detail. Based on the measured and the computed results, the applicability of Terzaghi method and Hewlett ＆ Randolph method were verified. Three-dimensional finite element analysis was also performed in this research; the computed orientation of maximum principal stresses, the stress level and the settlement pattern were analyzed in detail. Based on the test and numerical results, it is found that the value of stress reduction ratio computed by Terzaghi method is closed to that of Hewlett ＆ Randolph method; but the vertical stress distributions of the two methods are different considerably. If the failure surface observed from the numerical result is used, the prediction of vertical stresses using Terzaghi＇s method is found to be coincident with the measured value.

关 键 词：桩承式路堤 土拱效应 模型试验 有限元 

分 类 号：TU473[建筑科学—结构工程]