加筋土地基模型试验边界效应与承载性能分析  

Analysis of boundary effect and bearing capacity for reinforced soil model test

作　　者：王家全[1] 柏蕾 林志南 唐毅[1] WANG Jiaquan;BAI Lei;LIN Zhinan;TANG Yi(College of Civil Engineering and Architecture,Guangxi University of Science and Technology,Liuzhou 545006,China)

机构地区：[1]广西科技大学土木建筑工程学院,广西柳州545006

出　　处：《实验力学》2021年第1期133-142,共10页Journal of Experimental Mechanics

基　　金：国家自然科学基金项目(41962017);广西高等学校高水平创新团队及卓越学者计划项目(桂教人才[2020]6号);广西自然科学基金项目(2017GXNSFAA198170);广西研究生教育创新计划项目(YCSW2020222);广西高校中青年教师科研基础能力提升项目(2020KY08023);广西大学生创新创业训练计划资助项目(202010594035)。

摘　　要：为进一步探讨边界效应对加筋土地基的影响,基于室内方形基础下加筋土地基大模型试验,采用ABAQUS有限元软件建立加筋土地基数值模型,主要分析了模型宽度L和加载板宽度B对加筋土地基承载性能、地基内部土体应力应变及筋材变形的影响。结果表明:无筋地基与加筋土地基极限承载力均随L/B的减小而增大,当L/B>5时,可忽略边界效应对加筋土地基的影响;当L/B<2.67时,边界效应对加筋土地基的影响最大;当L/B>4时,边界效应对无筋地基的影响可忽略不计;加筋能够显著改善地基土体的不均匀沉降和减小基础两侧土体隆起高度;竖向应力分布区域随着B的增大而增大,加筋土地基受竖向荷载的影响宽度为5B,影响深度为2.57B~4B;当L/B>5时,不同L/B工况下土体变形、应力分布及格栅变形曲线基本重合,此时加筋土地基受边界效应的影响可忽略不计。Based on large-scale reinforced soil model tests under indoor square foundations,the ABAQUS finite element software is used to establish a numerical model of reinforced foundations,and the boundary effects on reinforced foundations are further explored.The effects of the model width L and the loading plate width Bon the bearing capacity of the reinforced foundation,the internal soil stress and strain and the deformation of the reinforcement are analyzed.The results show that the geogrid reinforcement can significantly improve the uneven settlement and height of the foundation soil.As the distance from the loading plate to the model increases,the ultimate bearing capacity of both reinforced foundation and unreinforced foundation increases.When L/Bis greater than 5,the boundary effect hardly influences the reinforced foundation;While when L/Bis less than 2.67,it will influence the reinforced foundation significantly.When L/Bis greater than 4,the boundary effect hardly influences the unreinforced foundation.The vertical stress distribution area increases with the increase of the loading plate width B.The affected width of the reinforced foundation under vertical load is 5B,and the affected depth is 2.57B~4B.When L/Bis greater than 5,the soil deformation,stress distribution and grid deformation curves are basically coincident,and the boundary effect on the reinforced foundation can be neglected.

关 键 词：加筋土地基 边界效应 有限元 极限承载力 影响范围 

分 类 号：TU443[建筑科学—岩土工程]