摘要
为研究某沿海下穿道路工程U型槽结构下碎石桩联合抗拔桩的抗浮效果,采用有限元软件ABAQUS建模,先分析振冲碎石桩对桩周土的挤土效应,将此振密挤密效果应用于抗拔桩侧阻力以及U型槽整体抗浮效果数值模拟分析中,结果表明:振冲碎石桩在单桩模型中桩周0.5 m范围以内挤土效应最强,桩周土体位移可达0.2 m,在群桩模型中桩周土体弹性模量能够得到较大的增强;与碎石桩实测荷载沉降曲线对比发现,数值模拟中采用初始桩半径0.2 m,膨胀位移0.2 m的参数设置能客观反映碎石桩挤密效应;整体模型数值模拟证实高水位砂性地层中振冲碎石桩联合抗拔桩的设计对U型槽抗浮效果最佳。结合规范中抗浮和沉降要求,U型槽底板的合理厚度宜为1.2 m。
In order to study the anti-floating effect of Vibroflotation Gravel Pile(VGP)combined with uplift pile under U-groove structure of a coastal underpass road project,the finite element software ABAQUS is used to analyze the soil compaction effect of VGP on the soil around the pile,and the vibroflotation compaction effect is applied to the numerical simulation analysis of lateral resistance of uplift pile and overall anti-floating effect of U-groove.The results show that the soil squeezing effect of VGP is the strongest within 0.5 m around the pile in the single pile model,and the displacement of soil around the pile can reach 0.2 m.In the pile group model,the elastic modulus of soil around the pile can be greatly enhanced.Compared with the measured load settlement curve of VGP,it is found that the parameter setting of initial pile radius of 0.2 m and expansion displacement of 0.2 m can objectively reflect the compaction effect of VGP.The numerical simulation of the overall model shows that the design of VGP combined with uplift pile in high water level sandy stratum has the best anti-floating effect on the U-shaped groove.Combined with anti-floating and the settlement requirements from the code,the appropriate thickness of the bottom plate is 1.2 m.
作者
李齐
陈东霞
Li Qi;Chen Dongxia(Department of Civil Engineering,Xiamen University,Xiamen,Fujian 361005,P.R.China;Xiamen Engineering Technology Center for Intelligent Maintenance of Infrastructure,Xiamen,Fujian 361005,P.R.China)
出处
《地下空间与工程学报》
CSCD
北大核心
2022年第S02期743-751,共9页
Chinese Journal of Underground Space and Engineering
基金
福建省自然科学基金(2021J01010,2021J02003)
关键词
振密挤密
抗浮效果
数值模拟
侧摩阻力
vibration and compaction
anti-floating effect
numerical simulation
side friction
