双层弹塑性地基水平受荷桩解析计算

Analytical calculation of laterally loaded piles in double-layered elastoplastic soils

目前关于双层弹塑性地基中水平受荷桩的解析计算研究相对较少。基于地基反力法和桩侧土体简化的弹塑性本构关系,推导了双层非均质弹塑性地基中桩顶自由水平受荷长桩的闭合形式解,得到了桩侧土体塑性区厚度、桩身最大挠度和最大弯矩的计算式。通过参数的特殊取值,所得解与现有单层地基中水平受荷桩的相关解完全一致,同时也验证了解析推导的正确性。算例分析表明本文解析解计算结果与三维有限元模拟结果及现场试验实测值吻合较好,可较有效地开展双层地基中水平受荷长桩的计算分析。

The analytical calculations of laterally loaded piles in double-layered elastoplastic soils are relatively few at present.Based on the subgrade reaction method and the simplified elastoplastic constitutive relations of soils beside the pile,the closed-form solutions for a free-head laterally loaded long pile in double-layered,non-homogeneous elastoplastic soils are deduced,and the formulas of the plastic zone thickness of the soil,the maximum deflection and moment of the pile are derived.When some parameters take special values,the present solutions are fully consistent with the existing solutions for the piles in one-layer soil,and the correctness of the present analytical derivation is verified meanwhile.The analyses of examples show that the results calculated by the proposed analytical solutions agree with those of 3D finite element analysis and field measurements,so the present method is capable of analyzing laterally loaded long piles in double-layered soils.