Performance of composite foundations with different load transfer platforms and substratum stiffness over silty clay  

作　　者：ZHANG Shuming LIU Yan YUAN Shengyang LIU Xianfeng JIANG Guanlu LIU Junyan 

机构地区：[1]School of Civil Engineering and Architecture,University of Jinan,Jinan 250022,China [2]The Engineering Technology Research Center for Urban Underground Engineering Supporting and Risk Monitoring of Shandong Province,Jinan 250022,China [3]School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China [4]Key Laboratory of High-speed Railway Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China

出　　处：《Journal of Mountain Science》2024年第5期1761-1774,共14页山地科学学报（英文）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.51878577 and 52378463);the Natural Science Foundation of Shandong Provincial,China(No.ZR2022ME042);the School-Enterprise Cooperation Program of China Railway 14th Bureau Group Co.(QTHT-HGLCHSD-00052)。

摘　　要：The semi-rigid pile-supported composite foundation is widely used in highway projects due to its effectiveness in increasing the bearing capacity and stability of foundations.It is crucial to understand the stress distribution across the embankment width and the behaviour of unreinforced foundations.Thus,five centrifuge tests were conducted to examine the bearing and deformation behaviours of NPRS(Non-Connected Piled Raft Systems)and GRPS(GeosyntheticReinforced Pile-Supported systems)with varying substratum stiffness,then a comparative analysis was conducted on embankment settlement,pressures underneath the embankments,and axial forces along the piles.The results indicated that greater substratum stiffness correlates with reduced settlement and deformation at various depths.Deformation occurring 5 meters from the embankment toe includes settlement in NPRS and upward movement in GRPS.The potential sliding surface is primarily located within the embankment in NPRS,whereas it may extend through both the embankment and foundation in GRPS.The pile-soil stress ratio and efficiency in NPRS are higher than in GRPS across the embankment.The axial force borne by end-bearing piles is significantly greater than that by floating piles.As the buried depth increases,the axial force in GRPS initially rises then declines,whereas in NPRS,it remains relatively constant within a certain range before decreasing.This study aids in assessing the applicability of composite foundations in complex railway environments and provides a reference for procedural measures under similar conditions.

关 键 词：Centrifuge modelling Composite foundation Failure mode Load transfer platform SUBSTRATUM STIFFNESS Silty clay 

分 类 号：U416.1[交通运输工程—道路与铁道工程]