PHC管桩水平承载性状分析

Lateral Bearing Mechanism of Prestressed High Strength Concrete Pipe Piles

利用大型通用有限元软件ABAQUS对深厚软土地基中预应力高强混凝土(PHC)管桩在水平荷载作用下的受力性能进行了数值模拟.桩土体系采用三维模型,桩身混凝土采用弥散开裂模型,管桩内钢筋采用理想弹塑性模型,桩周土体采用Mohr-Coulomb本构模型.桩土界面利用基于库伦摩擦模型的点面接触形式.桩中混凝土和桩周土体采用三维减缩积分一阶单元C3D8R,钢筋采用三维三节点杆单元T3D3.有限元分析结果与实测曲线比较接近,且基于库伦摩擦本构模型的点面接触形式可以很好地模拟在水平荷载作用下桩土的共同作用.利用经试验验证的有限元模型对不同型号PHC管桩的水平承载性能进行了分析,揭示了PHC管桩的水平荷载传递机理.

The bearing properties of prestressed high strength concrete （PHC） pipe piles under lateral loads are analysized by non-linear finite element program （ABAQUS）. The pile-soil system is modeled as three dimensional models. The concrete of pile is modeled as smeared cracking material while the Mohr-Coulomb Criterion is used to model the soil behavior. Bars in pile are modeled as classical metal plasticity material. The classical isotropic Coulomb friction model is used to model the interface friction contact between pile and soil through the element-based contact. 8-node linear bricks, reduced integration with hourglass control element （C3DSR） are employed to model the concrete of pile and the soil around the pile, while 3-node quadratic displacement truss element （T3D3） is employed to model the bars in pile. Results show that a good agreement is achieved between the numerical analysis and the test data. The classical isotropic Coulomb friction model can be used to model the interaction of the pile and the soil. Different type of PHC piles are analysized by the finite element method. The results will help to understand the bearing mechanism of PHC pipe piles under lateral loads.