螺杆桩细观工作机理离散元数值模拟

Discrete Element Numerical Analysis on Micro Work Mechanism of Half Screw Pile

螺杆桩属于异形截面桩,其与桩周土体间存在复杂的相互作用。采用基于离散单元法的二维颗粒流数值模拟技术,对砂土中承受竖向荷载的螺杆桩桩土荷载分担比、桩周土体位移场分布形态、土颗粒滚转特性、桩土接触力分布特征和孔隙率变化过程进行了细致研究,揭示了桩周土体细观结构参数变化规律及其与宏观力学行为表现之间的内在关联,从细观力学角度增进了对螺杆桩-桩土界面传力特性和桩周土体变形破坏演变过程的理解,为螺杆桩破坏模型和极限承载力计算方法确定提供了重要的理论依据。

The half screw pile belongs to the special-shaped pile between the pile and soil. The numerical simulation method of , there is a complex interaction existed two-dimensional particle flow code was adopted to investigate the load sharing ratio, soil displacement field distribution pattern, soil particle rolling characteristics, pile soil contact stress distribution and porosity change process of half screw pile subjected to vertical loading. The intrinsic connection between the mesoscopic structure parameter changes arid macroscopic mechanical responses is revealed. The understanding of the pile-soil interface friction transmission and soil progressive deformation failure process is enhanced from the viewpoint of mesomeehanics, which will provide an important theoretical basis for the determining of the failure mode and the ultimate bearing capacity calculation method for half screw pile.