大直径变截面桩竖向承载力及沉降算法研究

大直径变截面桩荷载传递机理复杂，传统桩基理论已不能恰当分析其工作机理和受力性能。针对此类问题，从大直径变截面桩的实际受力状态出发，通过分析桩体所受摩阻力和端承力的发挥情况划分桩体不同受力状态，在考虑一定安全储备的基础上选取其中一个临界状态进行研究，根据桩一土变形协调条件提出大直径变截面桩竖向承载力及沉降量的计算方法，并用该方法对苏通大桥变截面桩基础进行竖向承载力及沉降量计算，结果与通过试验得到的设计值十分接近，表明该方法比现行规范算法更准确。

Research on Algorithm for the Vertical Bearing Opacity and settlement of the Large Diameter Pile with Variable Cross-section

The load-transfer mechanism of the large diameter and variable cross-section pile is complex, while the traditional theory is not appropriate to analyze the mechanism of its load-bearing and deformation. Based on analysis of the development of the pile side friction and pile-end resistance, one of the critical states considering the safety of the reserves is studied. A method based on pile-soil deformation compatibility conditions is proposed, which can calculatethe vertical bearing capacity and settlement of the large-diameter and variable cross-section pile. USE this method is used to calculate the vertical bearing capacity and settlement of this type of pile of SuTong Bridge, and the result is very close to measured value.