摘要
采用同济大学中型岩土离心机进行了8组疏排桩-土钉墙组合支护基坑的离心模型试验。基于离心模型试验结果,提出了疏排桩-土钉墙组合支护基坑桩间土拱效应的最终形态分析模型,并结合三维有限元数值分析探讨了桩间土拱效应的动态发展过程以及桩间距和土钉参数对土拱形态的影响规律。研究结果表明:当桩间距与桩径之比B/D≥8或土钉长度与基坑开挖深度之比L/H≥2/3时,桩间土体无明显土拱效应;当桩间距与桩径之比B/D=4～6且土钉长度与基坑开挖深度之比L/H<2/3时,桩间土拱效应明显;疏排桩-土钉墙组合支护基坑的土拱最终形态表现为沿基坑顶面成抛物线形,延基坑深度方向具有一定直立深度的曲面。
Eight groups of centrifuge tests of pit foundation supporting with scattered piles and soil nailing were carried out by Tongji University.Based on the results of eight group tests,the analysis model of the final form of soil arching effect in pit supporting structure with scattered row piles and soil nailing was put forward.Not only the dynamic development process of soil arching effect between piles was explored,but also the effects of the pile spacing and soil nailing parameters on the soil arching pattern was analyzed in combining with three-dimensional finite element numerical simulation.The results show that,for pit supporting structure with scattered row piles and soil nailing,when the ratio of pile spacing to pile diameter is greater than 8or the ratio of soil nail length to the excavation depth is greater than 2/3,the soil between piles can not form soil arching effect.In addition,when the ratio of pile spacing to pile diameter is in the range of 4-6and the ratio of soil nail length to excavation depth is less than 2/3,the soil arching effect is obvious. Furthermore,for pit supporting structure with scattered row piles and soil nailing,the final form of soil arching effect is a curved surface,which along the top surface appears as parabolic and along the depthdirection has a certain vertical depth.
作者
古海东
罗春红
GU Hai-dong;LUO Chun-hong(Zhejiang Provincial Institute of Communications Planning,Design &Research,Hangzhou310006,China;Department of Road and Bridge,Zhejiang Highway Technicians College,Hangzhou 310023,China)
出处
《吉林大学学报（工学版）》
EI
CAS
CSCD
北大核心
2018年第6期1712-1724,共13页
Journal of Jilin University:Engineering and Technology Edition
基金
国家自然科学基金项目(40972179)
关键词
岩土工程
疏排桩
土钉墙
土拱效应
离心机模型试验
三维有限元分析
geotechnical engineering
scattered row piles
soil nail wall
soil arching effect
centrifuge model test
three-dimensional finite element analysis
