纵横向荷载作用下PHC管桩的有限元分析

FEM analysis of prestressed high strength concrete pipe piles under vertical and lateral loads

为研究纵横向荷载作用下PHC管桩的承载性能,通过经试验验证的有限元模型,考虑了地应力和桩土接触的影响,通过变换土体的参数、桩头自由长度、桩端土特性等影响管桩承载力的因素,对竖向和水平荷载共同作用下管桩的受力特性进行了分析。竖向荷载的作用能提高管桩的水平承载能力。同时,还分析了水平荷载对管桩竖向沉降的影响。在竖向荷载较小时,水平荷载的作用减小了桩顶沉降,但随着竖向荷载的增加,水平荷载对桩顶沉降的影响减小。分析结果表明,把竖向荷载和水平荷载分开来考虑管桩的受力性能是偏于安全的,不会引起太大的误差。

By considering the initial stress of soil and the contact between pile and soil,the response of a single pipe pile under the combined vertical and lateral loads was analyzed using the three-dimensional finite element model that was validated by the cases study.The influences of the soil parameters,the property of the soil at the toe of the pile and the unconstrained length of the pile have also been studied in the paper.The simulation analyses showed that the presence of vertical load reduced the lateral deflection.The influence of lateral load on the axial response of the pipe pile was studied,as well.The presence of lateral load reduced the vertical settlement when the vertical load was small,and when the vertical load increaseed,the influence of the lateral load decreased.Results showed that the approach that piles are separately analyzed for the vertical load and the lateral load is valid and safe.