Research On Behavior Of Reactive Powder Concrete-Filled Circular Steel Tube Stub Columns Under Axial Compression

Experiments on Reactive Powder Concrete-filled steel tube stub columns under axial compression are analyzed based on the research on concrete-filled steel tube and Reactive Powder Concrete at home and abroad. Finite element analysis on some specimens are carried out with ABAQUS, the main research results are as follows:(1) The experimental phenomena, load-strain curves and ultimate loading capacity of Reactive Powder Concrete -filled steel tube stub columns are analyzed based on the experimental results. The behavior of the columns in the experiments is summarized.(2) The nonlinear analysis models of two confined concrete models and two steel models are established with ABAQUS and one of them has the best agreements with the experimental results whose concrete model is presented by Han Linhai and steel model is ideal rigid-plastic model. The load-strain curves are in good agreements in the rising part before they arrive the peak point.(3) Two empirical formulas for estimating the ultimate loading capacity of Reactive Powder Concrete-filled steel tube stub columns are established based on the existing theory on normal concrete-filled and Reactive Powder Concrete-filled steel tube stub columns and the test data of 96 Reactive Powder Concrete-filled steel tube stub columns. It shows that the calculations with the empirical formulas were in good agreements with the experimental results.(4) An optimal design for a high-speed railway concrete-filled steel tube bridge is carried out with the good performance of Reactive Powder Concrete, the self-weight of the arch ribs can be reduced effectively in the new design. The quantity of concrete used in Reactive Powder Concrete is 36% lower than that of the original bridge and the quantity of steel used in Reactive Powder Concrete is 40% lower than that of the original bridge.