桩侧摩阻力-桩土相对位移试验曲线及其拟合分析  

Test curve of pile side friction-relative displacement of pile &soil and its fitting analysis

作　　者：包彦冉 马海龙[1] 雷珊珊[1] BAO Yanran;MA Hailong;LEI Shanshan(School of Civil Engineering and Architecture,Zhejiang Sci-Tech University,Hangzhou 310018,China)

机构地区：[1]浙江理工大学建筑工程学院

出　　处：《浙江理工大学学报（自然科学版）》2020年第1期102-108,共7页Journal of Zhejiang Sci-Tech University(Natural Sciences)

基　　金：国家自然科学基金项目（51878618）

摘　　要：为研究单桩不同加载方式对桩侧摩阻力-桩土相对位移规律的影响,通过粉土中桩底无土顶压桩、桩底有土顶压桩、底托桩、自平衡桩等的室内模型试验,得出不同加载方式下的桩侧摩阻力-桩土相对位移曲线(τ-s曲线)。对τ-s曲线的分析结果表明:桩侧平均摩阻力呈阶段性变化;桩底有土顶压桩达到极限摩阻力需要的桩土相对位移大于桩底无土顶压桩及底托桩;不同加载方式的单桩荷载传递均较好地遵循双曲线函数传递规律,通过两种方法拟合实测单桩桩侧摩阻力-桩土相对位移曲线,所得拟合τ-s曲线的拟合度大于0.98。此外,采用变形的双曲线函数进行线性函数拟合,比采用双曲线函数模型对τ-s曲线直接拟合得到的拟合度更高。In order to study the effect of different loading modes of single pile on pile side friction-relative displacement of pile and soil,the curves(τ-s curve)of pile side friction-relative displacement of pile and soil under different loading modes were obtained through laboratory model tests of top-pressed pile without soil at the end of pile,top-pressed pile with soil at the end of pile,bottom-supported pile and self-balanced pile in silt.The resultsofτ-s curveanalysis show that:theaveragefrictional resistance at the pile side changes in stages.The relative displacement of pile and soil required to reach the ultimate frictional resistance of the top-pressed pile with soil at the end of pileis greater than that of the top-pressed pilewithout soil at the end of pileand the bottom-supported pile.The load transfer of single pile under different loading modes well follows the transfer law of hyperbolic function.When the two methods were combined to fit the measurement of pile side frictionrelative displacement of pile and soil of single pile,the fittingdegree ofτ-s curve gainedis higher than 0.98.Besides,the fitting degree of deformed hyperbolic function used for linear fitting is higher than that of hyperbolic function model used for direct fitting ofτ-s curve.

关 键 词：模型试验 荷载传递函数 桩土相对位移 双曲线函数 

分 类 号：TU473.1[建筑科学—结构工程]