基于能量法的软土地基中基桩负摩阻力计算方法

摘要：为了有效计算与分析软土地基中基桩的受力与位移情况，采用土体弹塑性三折线模型计算桩侧土体的摩阻力与桩土相对位移；考虑桩侧土体发生沉降时桩-土保持能量平衡，导出产生负摩阻力时基桩的能量平衡方程，进而给出不同位移条件下桩身轴力与位移的计算式；最后通过对某工程实例进行数值计算表明：计算结果与实测数据基本一致，使用三折线模型的能量平衡计算式能够用于研究分析基桩在各级均布荷载作用下的受力特性，为桩基工程设计提供相应的参考。

Calculation of Negative Skin Friction on Single Pile in Soft Soil Foundation Based on Energy Method

Abstract: In order to effectively calculate and analysis the stress and strain of pile in soft soil foundation, soil elastoplastic three-phase segmented model is adopted to calculate the pile-soil relative displacement and skin friction. Considering when settlement of foundation soil is developed, pile and soil are keeping energy balance, so energy balance formulation of pile is deduced. Furthermore, formulas of pile-axial forces and shift in different pile-soil relative displacement condition are given out. Finally, through the numerical calculation of an engineering example and comparing its results with in-situ data, conclusions that the calculating results are substantial agreement with in-situ data, the energy balance formula using three-phase segmented model can analysis the stress attributes of pile in uniform load, and the calculating results can provide consultations to pile engineering design can be obtained.