逐级加载下水泥搅拌桩复合地基桩土应力的研究  

A Study of the Pile-soil Stress of Cement Mixing Pile Composite Foundation Under Step-by-step Loading

作　　者：陈致丞 刘红军[1] CHEN Zhi-cheng;LIU Hong-jun(School of Civil Engineering and Architecture,Wuyi University,Jiangmen 529020,China)

机构地区：[1]五邑大学土木建筑学院,广东江门529020

出　　处：《五邑大学学报（自然科学版）》2024年第2期64-71,共8页Journal of Wuyi University(Natural Science Edition)

基　　金：校企合作项目(HX21147)。

摘　　要：在工程中设计桩土复合地基的主要目的是充分发挥桩体承担荷载的效应,以达到变形协调的作用,桩土应力比是反映桩体加固效果的重要参数,为此探索桩土复合地基在逐级填土加载的过程中,桩身与桩间土所受应力的变化情况.本文以实际工程项目为依托,通过有限元建模计算,结合现场实测,研究桩土应力比的变化趋势.研究发现,桩土应力比在分级填筑的过程中会逐渐增加;在第三级填筑之前,路肩处桩土应力比大于路基中部;停止路堤填土后,桩土应力比曲线走势平稳,路基中部桩土应力比大于路肩处.桩体弹性模量对桩土应力比有显著影响,当桩体弹性模量从150 MPa增加至400 MPa,路基中部与路肩处桩土应力比最大值均有增加.The main purpose of designing pile-soil composite foundations in engineering is to give full play to the effect of the load borne by the pile body,so as to achieve deformation coordination and the pile-soil stress ratio is an important parameter reflecting the reinforcement effect of the pile body.In this study,the change of stress between the pile body and soil between in the process of loading by filling soil step by step is explored.Based on actual engineering projects,this paper studied the change trend of pile soil stress ratio through finite element modeling and field measurement.It was found that the stress ratio of pile to soil gradually increased during the process of graded filling.Before the third grade filling,the pile-soil stress ratio at the road shoulder was greater than that in the middle of the roadbed.After stopping embankment filling,the curve of pile-soil stress ratio was stable,and the pile-soil stress ratio in the middle of the roadbed was greater than that at the road shoulder.The pile elastic modulus had a significant influence on the pile-soil stress ratio.When the pile elastic modulus increased from 150 MPa to 400 MPa,the maximum value of the pile-soil stress ratio at the middle of the roadbed and at the shoulder both increased.

关 键 词：逐级加载 水泥搅拌桩 复合地基 桩土应力比 有限元模拟 

分 类 号：U416.1[交通运输工程—道路与铁道工程]