临坡段挖井基础承载能力及嵌固稳定性分析  

Analysis of the bearing capacity and embedded stability of digging well foundation in the slope section

作　　者：姚伦波 李世文 李增源 张加兵 马少坤[2] YAO Lunbo;LI Shiwen;LI Zengyuan;ZHANG Jiabing;MA Shaokun(Guangxi Communications Investmen Group Co.,Ltd.,Nanning 530022,China;School of Civil and Architectural Engineering,Guangxi University,Nanning 530004,China)

机构地区：[1]广西交通投资集团有限公司,广西南宁530022 [2]广西大学土木建筑工程学院,广西南宁530004

出　　处：《广西大学学报(自然科学版)》2025年第1期15-27,共13页Journal of Guangxi University(Natural Science Edition)

基　　金：国家自然科学基金项目(52108367);广西科技基地和人才专项(桂科AD21238018)。

摘　　要：为了进一步研究临坡段挖井基础承载能力及稳定性,依托乐业至望谟高速公路运赖特大桥左幅10#挖井基础工程实际,通过ABAQUS软件建立桥墩挖井基础岩土体耦合作用的三维有限元模型,探讨了不同坡度和基础埋深下挖井基础的承载能力和嵌固稳定性,并根据基础沉降限值评估不同工况下挖井基础的安全性。结果表明,挖井基础水平变形与荷载等级的增长呈正相关,以斜坡挖井基础深度H=9 m为例,最后3级荷载等级对应基础总水平位移分别占总变形的47.49%、50.57%、53.43%,且随坡度的增加以及挖井基础深度的减小水平变形逐渐增加,以坡度β=10°为例,对比基础埋深为17 m的水平变形,随着基础深度H不断减小,基础水平变形的减小程度分别为1.89%、5.84%、14.43%和25.83%。同时,挖井基础桩侧摩阻力与基础深度的增长呈负相关,与坡度的增长呈正相关。此外,在同一坡度下,基础埋深越大土侧压力峰值越大,基础埋深为13 m,土侧压力峰值比埋深为9 m时峰值大46%。最后,基础所处位置坡度的增加降低了挖井基础深度所带来的稳定性和抗倾覆能力,在设计过程中,选择地势平缓区域以及基础深度为13 m能有效减小基础水平沉降以及桩侧摩阻力的增长。In order to further study the bearing capacity and stability of the excavation foundation in the slope section,a three-dimensional finite element model of the coupling effect of bridge pier,excavation foundation and rock and soil mass was established by ABAQUS based on the actual engineering of the 10#excavation foundation on the left width of the Yunlai Bridge on the Leye Wangmo Expressway.The bearing capacity and embedding stability of the foundation under different slopes and foundation depths were discussed,and the safety of the foundation under different working conditions was evaluated according to the foundation settlement limit.The results show that the horizontal deformation of the foundation is positively correlated with the growth of the ultimate load grade,taking slope excavation foundation depth H=9 m as an example,the total horizontal displacement of the foundation caused by the last three load levels accounts for 47.49%,50.57%and 53.43%of the total deformation respectively,and the horizontal deformation gradually increases with the increase of slope and the decrease of the depth of the digging foundation,taking slope angleβ=10°as an example,with the continuous decrease of the foundation depth H,the reduction rate of the horizontal deformation of the foundation caused by the last level of load level is 1.89%and 5.84%,respectively,14.43%and 25.83%.At the same time,the lateral friction resistance of the pile of the excavation foundation is negatively correlated with the growth of foundation depth,and positively correlated with the growth of slope.In addition,under the same slope,the higher the buried depth,the higher the peak soil side pressure,the higher the foundation depth of the soil side pressure peak,the peak soil side pressure of the foundation buried depth of 13 m is 46%higher than the peak depth of 9 m.Finally,the increase of the slope of the foundation reduces the stability and anti-overturning ability brought by the depth of the digging foundation,and in the design process,the selection o

关 键 词：挖井基础 承载能力 耦合作用 水平变形 侧摩阻力 基础沉降 

分 类 号：U442[建筑科学—桥梁与隧道工程]