Experimental And Theoretical Research On The Seismic Behavior Of Hollow Ordinary Concrete And Recycled Aggregate Concrete Fillied Stell Tubular Columns

Concrete filled steel tube is a kind of combination component which is made of steel tube filled with concrete. Hollow cncrete filled steel tube is a hollow component made by centrifugal casting concrete and through steam curing. CFT due to the interaction of two kinds of materials, with high bearing capacity, plastic and seismic performance is good, etc.Based on the mechanical characteristics of frame column, we give the experimental and theoretical research of the seismic behavior of hollow steel tube filled with ordinary concrete and recycled aggregate concrete. We put forward the skeleton curves theory model of the HCFT frame column with the experiment and theoretical analysis results. The simplified calculation method of displacement ductility coefficient is given too. Research results can provides reliable experimental and theoretical basis for structural elasto-plastic seismic analysis and seismic design.There are two circular hollow ordinary cncrete filled steel tubal columns and a hollow recycled aggregate concrete filled steel tubal column have conducted the hysteretic behavior test study under a constant axial force and low cyclic horizontal load. Then we analyze and evaluate their seismic performance indexes, such as destructive patterns, skeleton curves, energy consumption, displacement ductility, etc.P-Δskeleton curves is a intuitive reaction of loading and ductility feature strength changes about structure in the whole process, also is a important basis to measure its earthquake-resistant performance. Finite element analysis are carried on the skeleton curves of the specimens, and the results are in good agreement with the experimental results. A series of parametric analysis are conducted on the curves, such as axial compression ratio, hollow rate, slenderness ratio and so on.Theoretical research of HCFT frame column are carried by using energy method and limit equilibrium theory method. A three-stage skeleton curve theory model of HCFT column is provided, the calculation of parameters about every stages is given too. Finally, the simplified calculation method of displacement ductility coefficient is proposed.By comparing with the skeleton curves of the ordinary concrete components and recycled ones, analyses the seismic performance of hollow recycled concrete filled steel tube bending components. Seleton curve theory model and the displacement ductility coefficient calculation method of them are proposed based on the ordinary concrete ones.