用荷载传递函数法计算单桩承载力  

Using Load-transmission Function Method in Single Pile Bearing

作　　者：聂更新[1] 陈枫[1] 

机构地区：[1]中南大学土建学院,湖南长沙410083

出　　处：《土工基础》2004年第2期29-32,45,共5页Soil Engineering and Foundation

基　　金：湖南省自然科学基金资助 ( 0 2JJY40 5 0 )项目

摘　　要：根据位移协调理论 ,采用荷载传递函数法分析了竖向受荷下单桩的承载特性。桩侧传递函数采用双曲线模型 ,然后用剪切变形传递理论对该双曲线参数a ,b进行修正 ,根据桩身各单元体位移与内力的协调关系 ,确定桩顶荷载与位移的关系曲线。利用已知土力学参数 ,对工程实例进行了数值计算 ,计算得到的桩极限承载力为4 4 5 8kN ,与工程实测值 4 6 5 4kN相吻合 ,相对差值仅为 4 % ,验证了用剪切变形传递理论修正双曲线参数的正确性。此外 ,还在不同土力学参数条件下 ,研究了单桩荷载传递的一些基本特性。研究表明 :桩的沉降量随混凝土强度的增加而减小 ;承载力和桩侧摩阻力随长径比的增大而增大 ;桩侧摩阻力还随土弹性模量Es 值的增加而增大。Based on the displacement coordinate theory, the capacity of single pile under down-ward loading was analysed by using the load transmission function. A hyperbola modelis is used for the load transmission function between pile and surrounding soil, in which the parameters, a and b, are modified by shear deformation transmission theory. The curve for load versus displacement at pile top can be obtained through coordinate relation between element displacement and inner force of a pile. The numerical calculation was conducted on an engineering example using the mechanical parameters of in-situ soil. The ultimate bearing capacity of the pile in this case is 4458kN, comparing the in-situ testing value 4654kN, the relative error is only 4%. This method is proved to be of high precision.

关 键 词：荷载传递函数 位移协调 土力学参数 单桩 承载力 

分 类 号：TU473.11[建筑科学—结构工程]