Study of axial compression performance of prestressed steel strand ultra-high strength concrete pipe piles

DOI：10.7511/dllgxb201806011

 作者 单位 陈刚,周清晖,徐铨彪,龚顺风,肖志斌,刘承斌

通过对2种常用桩型的预应力钢绞线超高强混凝土管桩和预应力钢绞线复合配筋超高强混凝土管桩进行轴压性能试验、数值模拟分析和经验公式计算，研究了管桩的极限轴压承载力、极限轴压变形及破坏特征．结果表明：所有管桩试件均呈现受压破坏，混凝土首先压碎，导致纵筋向外压曲，箍筋拉断．数值模拟得到的桩身破坏断面与试验桩身破坏断面吻合较好，数值模型可以较为准确地预测管桩极限轴压承载力和极限轴压变形．预应力钢绞线超高强混凝土管桩以及预应力钢绞线复合配筋超高强混凝土管桩的抗压承载力建议按照国家标准图集《预应力混凝土管桩》(10G409)中公式进行计算．

Through axial compression performance experiments, numerical simulations and empirical formula calculations of two types of commonly-used piles, including prestressed steel strand ultra-high strength concrete pipe piles and prestressed steel strand composite reinforcement ultra-high strength concrete pipe piles, the ultimate axial compression bearing capacity, deformation capacity and damage characteristics of pipe piles were investigated. The results show that all of the pipe pile test specimens are compressive failure, and the concrete is crushed at first, which leads to the outward compression of longitudinal bars and the breaking of stirrups. The numerical simulation results of the failure surface of pipe piles are in good agreement with the experimental results, and the numerical model can accurately predict the ultimate axial compression bearing capacity and deformation capacity of the pipe piles. It is recommended that the empirical formula in national standard atlas 10G409 ″prestressed concrete pipe pile″ could be used to calculate the compression bearing capacity of prestressed steel strand ultra-high strength concrete pipe piles and prestressed steel strand composite reinforcement ultra-high strength concrete pipe piles.