摘要
为研究钙质砂地基中群桩基础承载过程中的性能特征,开展不同桩距条件下群桩基础静载试验.得到不同桩距条件下群桩的Q-S曲线和S-lgt曲线,测得3d、4.5d、6d(d为桩径)群桩在静载条件下的极限承载力F_(u),研究各个桩段的桩身轴力、桩侧摩阻力以及桩端阻力的变化趋势.研究结果表明:群桩的Q-S曲线为缓变型,S-lgt曲线为渐变型,桩基承载变形大致分为稳定、渐进以及破坏3个阶段,相较于3d群桩,4.5d、6d群桩沉降发展更缓慢,F_(u)更高;同等桩距下,钙质砂地基表现出比陆源砂地基更强的群桩效应,钙质砂地基中群桩最佳桩距应在4.5d~6d之间.该研究为群桩在钙质砂地基中的应用提供数据支撑和理论参考.
In order to study the performance characteristics of pile group foundation in the bearing process of calcareous sand foundation,the static load test of pile group foundation under different pile spacing conditions is carried out.The Q-S curve and S-lgt curve of pile group under different pile spacing conditions are obtained,and the ultimate bearing capacity F_(u) of 3d,4.5d and 6d(dis pile diameter)pile group under static load conditions is measured.The trend of pile axial force,pile side friction and pile end resistance of each pile section is studied.The results show that the Q-S curve of the pile group is a slow change type,and the S-lgt curve is a gradual change type.The bearing deformation of the pile foundation is roughly divided into three stages,i.e.the stable stage,the progressive stage and the failure stage.Compared with the 3d pile group,the settlement of the 4.5d and 6d pile groups develops more slowly,and the F_(u) ultimate bearing capacity is higher.Under the same pile spacing,the calcareous sand foundation shows a stronger pile group effect than the terrestrial sand foundation,and the optimal pile spacing of the pile group in the calcareous sand foundation should be between 4.5d~6d.This study provides data support and theoretical reference for the application of pile groups in calcareous sand foundation.
作者
王瑞红
王辉
骆浩
王芳
WANG Ruihong;WANG Hui;LUO Hao;WANG Fang(Key Laboratory of Geological Hazards in Three Gorges Reservoir Area,Ministry of Education(China Three Gorges University),Yichang 443002,China;College of Civil Engineering and Architecture,China Three Gorges University,Yichang 443002,China;PowerChina Guiyang Engineering,Co.,Ltd.,Guiyang 550081,China)
出处
《三峡大学学报（自然科学版）》
CAS
北大核心
2024年第3期64-69,共6页
Journal of China Three Gorges University：Natural Sciences
基金
国家自然科学基金面上项目(51979151)
湖北省自然科学基金杰青项目(2021CFA090)
三峡大学三峡库区地质灾害教育部重点实验室开放基金项目(2020KDZ07)。
关键词
钙质砂地基
混凝土群桩
模型试验
承载特性
calcareous sand foundation
concrete pile group
model test
load bearing characteristics
