液化土侧向扩展对具有轴向力单桩的变形影响

Lateral Spreading Influence on Deformation of Single Pile in Liquefaction Soils

将地震液化场地土层分为表层的非液化土层,中部的液化土层以及底部的基础层,利用表层的非液化土层的土压力和液化土层及基层的Winkler模型,采用拟静力分析方法,建立了考虑上部结构对桩基产生的轴力和液化土侧向扩展共同作用下单桩水平变形的简单Euler梁模型,给出了问题的解析封闭解。计算结果与实验结果吻合较好,说明了封闭解的合理性。在此基础上,分析了各种参数对桩基变形响应的影响,结果表明:相比于液化土层的侧向扩展位移,桩的抗弯刚度、液化土层刚度以及轴力等参数对桩基力学性能具有较大影响,这些结果可以为工程设计提供一定的参考依据。

Soil profile in liquefied deposits is divided into three layers： a non-liquefied crust layer at the ground surface, a liquefied layer in the middle of the deposit and a non-liquefied base layer. The effect of the soil deposit on a pile was described by lateral earth pressure for a non-liquefied crust layer and Winkler model for liquefied and base layer. Considering the axial load caused by the superstructure and lateral spreading of the liquefied soil, a simply Euler beam model was established for a pile in the liquefied soil deposit by pseudo-static method, and a closed form solution was obtained, which gave numerical results in good agreement with the experimental ones. The influences of the various parameters on the behavior of the pile was investigated, and it shows that, comparison with the lateral spreading, the bending stiffness, rigidity of the liquefaction soil layer and the axial load have great influences on the behavior of the pile.