路堤下刚性桩复合地基稳定性分析方法研究  

Research on the Stability Analysis Method of Rigid Pile Composite Foundation under Embankment

作　　者：张东卿[1] 薛元[1] 罗强[2] 姜浩[2] 马宏飞 ZHANG Dongqing;XUE Yuan;LUO Qiang;JIANG Hao;MA Hongfei(China Railway Eryuan Engineering Group Co.Ltd,Chengdu,Sichuan 610031,China;Southwest Jiaotong University,Chengdu,Sichuan 610031,China)

机构地区：[1]中铁二院工程集团有限责任公司,成都610031 [2]西南交通大学,成都610031

出　　处：《铁道工程学报》2021年第7期6-11,共6页Journal of Railway Engineering Society

基　　金：四川省科技厅重点研发项目(2018GZ0050);中铁二院工程集团有限责任公司科研项目(KYY2019141(19-21))。

摘　　要：研究目的:现阶段刚性桩复合地基稳定分析理论工作落后于工程实践,亟需开展路堤下刚性桩复合地基失稳破坏特性及稳定分析方法研究,建立与刚性桩复合地基破坏模式相匹配的稳定分析方法。研究结论:(1)刚性桩复合地基的失稳破坏模式包括滑移破坏、弯拉破坏、弯压破坏、倾覆破坏以及桩间土绕流破坏;(2)刚性桩复合地基可采用基于破坏模式的稳定性分析方法:计算各种破坏模式对应的抗滑力,其中的最小值即为桩体能够提供的抗滑力,将最小抗滑力代入极限平衡法公式中,即可获得基于破坏模式的稳定系数;(3)刚性桩复合地基边坡至路肩附近位置,桩体以弯折破坏为主,宜增强桩身刚度或加强桩顶横向连系增强稳定性;路堤中心位置的桩以绕流破坏为主,宜缩小间距或者加大桩帽;(4)本研究结论可为工程实践和规范修订提供参考。Research purposes:At this stage,the theoretical research on stability analysis of rigid pile composite foundation lags behind the engineering practice.It is urgent to carry out research on the failure characteristics and stability analysis method of rigid pile composite foundation under embankment.This paper aims to establish a stability analysis method that matches the failure mode of rigid pile composite foundation.Research conclusions:(1)The instability failure modes of rigid pile composite foundation are summarized as:slip,bending and tension,bending and compression,overturning,and soil flow between piles.(2)The method based on failure mode can be used for stability analysis of rigid pile composite foundation:the slip resistance corresponding to each failure mode was calculated,and the minimum value was the slip resistance that the pile could provide,and by substituting the minimum anti-slid force into the limit equilibrium equation,the stability safety coefficient based on the failure mode can be obtained.(3)It is advisable to increase the rigidity of pile or strengthen the lateral connection of piles to increase the stability where the bending failure mode is the most likely to happen;the space between piles should be reduced or the pile cap should be enlarged to prevent the soil flow around piles.(4)The research conclusion can provide a theoretical basis for engineering practice and revision of specification.

关 键 词：刚性桩 复合地基 破坏模式 稳定性 分析方法 

分 类 号：U213.1[交通运输工程—道路与铁道工程]