Behavior of a concrete filled steel box column with considering detachment under seismic load

Various numerical studies have been conducted on the dynamic behavior of concrete-filled steel columns. However, the detachment caused by the tensile stress between the steel plates and the concrete is rarely considered. This paper describes the results of dynamic numerical analysis conducted on a concrete-filled steel box column used as a pier of a motorway viaduct under seismic load, with detachment considered as a contact problem. The results obtained indicate that detachment causes large residual displacement and reduces the peak load of the column. Further, the influence of the detachment on column behavior is shown to depend on the depth of the concrete.