考虑桩体损伤的PHC管桩复合地基变形与稳定性分析

依托普洱车站软弱地基上的超高填方工程,采用ABAQUS中的混凝土损伤塑性模型构建了路堤荷载下考虑桩体损伤的PHC管桩复合地基的三维数值模型,探讨了PHC管桩桩体的变形特征,并根据边桩特征点的侧向变形分析其稳定性。结果表明:采用PHC管桩复合地基可显著控制路堤变形;且相较于常规的线弹性模型,采用混凝土损伤塑性模型可较好地反映PHC管桩刚度退化后的变形特征,并能合理确定PHC管桩复合地基的安全系数。

Deformation and Stability Analysis of PHC Pipe Pile Composite Foundation with the Consideration of Damages to Pile Body

Based on the super high fill engineering on the soft foundation at Pu’er Station, by use of the concrete damage plasticity model in ABAQUS, a three-dimensional numerical model of PHC pipe pile composite foundation with the consideration of damages to the pile body under the embankment load, was constituted, by which the deformation characteristics of PHC pipe pile body was discussed, and the stability thereof was analyzed according to the lateral deformation at the feature point of side piling. The results show that PHC pipe pile composite foundation may control the embankment deformation significantly; and compared to conventional linear elastic model, the concrete damage plasticity model used may well reflect the deformation characteristics of PHC pipe pile after stiffness degeneration, and determine the safety coefficient of PHC pipe pile composite foundation reasonably.