| So far, many of researches on mechanical property of concrete filled steel tube (CFT) under quasi-static load have been carried out, but few efforts have been focused on CFT under impacting and blasting load. In this paper, drop hammer machine was used to study the performance of CFT short columns under impact load; as a favorable supplement for experiments, numerical simulation was conducted using famous FEA software LS-DYNA. The main jobs as follow:(1) CFT short columns with two different thickness of steel tube and plain concrete short columns were tested under different impact energy by drop hammer machine, impact force history, strain history of specimens surface and deformation were measured and recorded, and a high speed camera was used to record the whole damage process of specimens.(2) Load vs. deformation curves and deformation patter under impact load were analyzed and compared with that under static load, the influence of impact energy on deformation, the maximum impact force and its duration was discussed, and a comparison was made on performance between CFT and plain concrete short columns under impact load.(3) After analyzing energy transfer in impacting process and the relation between the maximum impact force and the static bearing capacity, based on reasonable simplifying for load vs. deformation loop under impact load, the required static bearing capacity for CFT columns against impact load can be evaluated using the proposed simple equation, namely, a simple impacting-resistant design method.(4) Numerical simulation was conducted on impact tests using universal FEA software LS-DYNA, MAT_JOHNSON_HOLMQUIST_CONCRETE material model was employed to simulating core concrete, simulation results such as impact force, deformation and strain of steel tube surface were consistent with test results, in the end, energy transfer and core concrete failure mechanism under impacting were discussed.
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