新桩贯入对邻近再利用既有桩的影响  

Influence of New Pile Penetration on Adjacent Reused Pile

作　　者：崔纪飞 饶平平[1] 李镜培[2] Cui Jifei;Rao Pingping;Li Jingpei(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China;College of Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]上海理工大学环境与建筑学院,上海200093 [2]同济大学土木工程学院,上海200092

出　　处：《吉林大学学报（地球科学版）》2021年第5期1506-1513,共8页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(41972274)。

摘　　要：采用理论分析的方法,首先基于半无限土体中改进的球孔扩张理论,求解新桩沉桩挤土效应引起的土体位移场。然后将其作为已知条件施加于邻近既有桩,分析既有桩变形和内力变化规律,探讨既有桩桩端约束条件、桩身刚度及土体模量对既有桩响应的影响;同时结合数值分析,对本文理论方法进行验证。最后分析了新旧桩之间距离和新桩半径对挤土效应引起的既有桩变形和内力的影响。结果表明:桩端约束形式仅影响桩端附近桩身变形;随着新旧桩之间距离的增加,既有桩变形和内力显著减小;随着桩径的增加,既有桩变形和内力均逐渐增大。最后提出采用远离既有桩和采用长细桩的措施来降低新桩施工对既有桩的影响。The cavity expansion theory of semi-infinite soil is adopted to obtain the displacement field of soil caused by the new pile driving, and then it is applied to the existing pile based on the two-stage method to analyze the deformation and internal force changes of the existing pile. The constraint condition of the existing pile bottom, the rigidity of the pile body, and the soil modulus on the response of the existing pile was studied, meanwhile, the theoretical method was verified by using the numerical analysis, and also the influence of the distance between the new and used piles and the radius of the new piles was analyzed. The results show that the constraint of the pile tip only affects the deformation of the pile body near the pile tip: With the increase of the distance between the new and old piles, the deformation and internal force of the existing piles decrease significantly;The deformation and internal force of the existing pile increase gradually with the increase of the new pile diameter. The measures to stay away from existing piles and using long and thin piles are proposed to reduce the impact of new pile construction on existing piles.

关 键 词：既有桩 再利用 贯入 挤土位移 变形 

分 类 号：TU473[建筑科学—结构工程]