Particle flow code numerical simulation of bearing mechanism for PCC pile under vertical load
CHEN Yadong;CHEN Si;YU Yan;LIU Ye;SHE Yuexin;Faculty of Architecture and Civil Engineering,Huaiyin Institute of Technology;Jiangsu Research Institute of Building Science Co. Ltd;Jiangsu Huaian Architecture Design Institute Co. Ltd;
In order to further reveal the mesoscopic interaction mechanism of a cast-in-situ concrete thin-wall pipe pile,the load transfer mechanism,the inside and outside soil displacement field distribution character,and the mesoscopic structure parameters change rule in PCC pile-soil interaction process,are studied by the two-dimensional particle flow numerical simulation technology. The results of numerical analysis show that the bearing capacity of a PCC pile is mainly controlled by the outer friction resistance,that the out friction resistance of a PCC pile has always been significantly higher than the inner friction resistance,and that the inner soil bearing capacity is insufficient. The outer friction resistance of a PCC pile plays more fully at the central region and pile tip,but it is weakened obviously at the 0. 65 L penetration depth. The soil displacement vector inside a PCC pile is lesser at pile upside scope; the soil particles in the range above 3d1 pile tip happens stab deformation together with pile body because of the soil plug effect; the outside soil displacement vector of pile body in central influence scope reaches 2d; the entire pile outside displacement affected zone presents a circular arc distribution; and contact force and porosity variations of soil inner and outer pile are consistent with PCC pile macro mechanical performance. The results are important for further clarification of PCC pile-soil interactions.