Research On The Seismic Behavior Of Prestressed Centrifugal Concrete Filled Steel Tubular Piles(PSC Pile)

Centrifugal concrete filled steel tube pipe pile(SC pile)is a kind of hollow composite component,which is a steel pipe made from crimped and welded steel plate(or strip)filled with concrete before centrifugal forming and steam curing.SC pile combines the characteristics of steel and concrete,taking the advantages of high bearing capacity,good plasticity and good toughness.Therefore,scholars at home and abroad have paid more and more attention to its research.Prestressed SC pile(PSC pile)is an application of pretensioning method on SC pile,which makes the performance of high strength concrete be utilized more efficiently,taking the advantages of steel pipe pile and prestressed pipe pile.As a new type of foundation pile,there has been little research on its seismic performance.In order to study the seismic performance of PSC pile,the following work has been done,and some results and conclusions are obtained:Design and complete the low cyclic loading test of SC pile and PSC pile,obtaining the loading-displacement hysteretic curve of each specimen.Analyze and compare some seismic performance indexes of specimens such as failure characteristic,skeleton curve,ductility,energy dissipation,stiffness degradation and strength degradation.The results indicate that the energy dissipation capacity of SC pile is close to that of PSC pile,while the seismic bearing capacity of PSC pile is higher than that of SC pile.Simulate the seismic performance test of SC pile and PSC pile using ABAQUS on the basis of the experiment,obtaining the hysteretic curves,skeleton curves,stiffness degradation curves and bearing capacity degradation curves.The numerical simulation results was found to agree well with the experimental results by comparison between experimental and simulated curves,which indicates that the SC pile and PSC pile model is accurate enough to precisely simulate the actual loading process of concrete filled steel tube structure.Through the validated fem model,analyze the effects on PSC pile flexural member by parameters such as thickness of steel tube wall,thickness of concrete wall,diameter of pipe,strength of steel tube,strength of concrete,prestressed reinforcement ratio and axial compression ratio.Finally,summarizes the full text and put forward the prospects.