不同加筋方式下碎石桩复合地基承载性能试验研究  

Experimental study on load bearing performance of stone columns under different reinforcement methods

作　　者：李丽华 曹毓[1,2] 刘巨强 肖衡林 张东方 刘一鸣[1,2] LI Lihua;CAO Yu;LIU Juqiang;XIAO Henglin;ZHANG Dongfang;LIU Yiming(School of Civil Engineering,Architecture and Environment,Hubei University of Technology,Wuhan,Hubei 430068,China;Ecological Road Engineering Research Center,Hubei University of Technology,Wuhan,Hubei 430068,China)

机构地区：[1]湖北工业大学土木建筑与环境学院,湖北武汉430068 [2]湖北工业大学湖北省生态道路工程技术研究中心,湖北武汉430068

出　　处：《岩石力学与工程学报》2023年第12期3085-3094,共10页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52278347);湖北省重点研发计划项目(2022BCA059);国家自然科学基金联合基金重点项目(U22A20232)。

摘　　要：制作一套碎石桩复合地基室内模型试验装置,开展11组加筋碎石桩复合地基室内模型试验和2组未加筋对比试验,以研究不同包裹长度、加筋间距及加筋组合方式下复合地基承载能力、桩土应力比、承载能力改善率和桩体鼓胀变形情况。试验结果表明:相比较传统碎石桩,筋材的加入对复合地基承载力有明显提升,全长包裹的垂直加筋提升效果最为显著;复合地基承载力提升较大的加筋方式对应的承载能力改善率和桩土应力比值较大,承载能力改善率随加筋长度和加筋间距的增加而增大;复合地基的桩土应力比值随沉降增加呈现出一定幅度的波动,并随加筋间距缩小和加筋长度增加而增大;不同加筋方式下桩身变形规律存在一定差异,采用全长包裹的垂直加筋方式下,桩体鼓胀变形较为均匀且变形量小,对复合地基承载能力的提升以及桩体鼓胀变形的抑制效果更佳。A set of indoor model test device for gravel pile composite foundation was fabricated,and 11 groups of indoor model tests of reinforced gravel pile composite foundation and 2 groups of unreinforced comparison tests were carried out.The composite foundation bearing capacity,pile-soil stress ratio,bearing capacity improvement rate and pile bulge deformation under different parcel lengths,reinforcement spacings and reinforcement combination methods are researched.The test results show that compared with the traditional gravel pile,the bearing capacity of the composite foundation is significantly improved by reinforcement,and the vertical reinforcement effect of the full-length wrapped is the most significant.The reinforcement method with larger composite foundation bearing capacity improvement corresponds to larger bearing capacity improvement rate and pile-soil stress ratio.The improvement rate of bearing capacity increases with the increase of reinforcement length and reinforcement spacing.The pile-soil stress ratio of the composite foundation fluctuates with the increase of settlement.And increases with the reduction of reinforcement spacing and the increase of reinforcement length;There are some differences in the deformation law of pile body under different reinforcement methods.The bulging deformation of pile body with full-length wrapped vertical reinforcement method is relatively uniform and the deformation is small,which has better effect on improving the bearing capacity of composite foundation and inhibiting the bulging deformation of pile body.

关 键 词：桩基础 碎石桩复合地基 加筋方式 模型试验 桩土应力比 鼓胀变形 

分 类 号：TU47[建筑科学—结构工程]