(1. School of Civil Engineering and Transportation,South China University of Technology,Guangzhou,Guangdong 510641,China;2. Shenzhen Government Investment Project Evaluation Center,Shenzhen,Guangdong 518036,China;3. Shenzhen Geotechnical Investigation and Surveying Institute Co.,Ltd.,Shenzhen,Guangdong 518028,China)
Abstract:Foundation pit excavation in the building compact district of urban will absolutely induce soil lateral movement,which may generate the additional deflections and bending moments in the adjacent pile shaft,and may lead to their superstructures distress,even failure. To avoid the drawbacks of three-dimensional numerical analysis,such as complexity modeling and time consuming,the two-stage method(TSM) is presented for determining the behavior of adjacent pile caused by foundation pit excavation. Firstly,the additional lateral displacement of soil mass due to adjacent foundation pit excavation is calculated by the virtual image technique. Secondly,the governing differential equations are built up based on Winkler model and their analytical solution of matrix is derived. Finally,analysis of case histories show that the calculated results of analytical solution are reasonable and could be used to analyze the influence of excavation on adjacent pile foundations.
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