The Research On The Seismic Behavior Of Centrifugal Concrete Filled Steel Tubular Pile

Centrifugal concrete-filled steel tube pipe pile (SC pile) is a kind of hollow composite member made by casting concrete centrifugally and curing in steam. SC pile has a good application prospect because of combining the characteristics of steel tube and concrete, so domestic and international scholars have given more attention on the research and application of it. Study on the seismic behavior of SC pile is rare and scarce in China, which severely limits the popularization and application of SC pipe pile. The following researches have been done on the seismic behavior of SC pile and some results and conclusions were obtained:The load-displacement hysteretic loop curve of SC pile, pre-stressed SC pile and PHC pile is obtained by low-cycle loading experiments. The analysis and comparison of the failure mode and the seismic behavior indexes like skeleton curve, ductility, energy dissipation capacity and stiffness shows that the seismic performance of SC pile is significantly better than PHC pile, but adding prestressing tendons in SC pile will not improve the seismic performance significantly.ABAQUS was used in finite element simulation of the seismic performance of SC pile based on the experiments. The results of the simulation agree well with the experiment data, which indicates that the numerical model is comparatively accurate. Using the validated finite element program, the influence of wall thickness, diameter and material strength to the load-displacement skeleton curve of flexural members in SC pile was analyzed.Combining the experimental and finite element analysis results, trilinear theoretical model of skeleton curve of flexural members in SC pile was proposed. The simplified calculation method of parameters in this model was deduced through theory. The comparative analysis of the curves calculated through theory and obtained by experiments verifies that this model can perfectly reflects the real skeleton curve of members.Finally, the follow-up study of this topic was looked forward based on the summary of the paper.