CIRCULAR DOUBLE SKIN STAINLESS STEEL TUBULAR COLUMN FILLED WITH UHPFRC SUBJECTED TO IMPACT LOAD

Concrete filled steel tube (CFST) column is an important type of structural member and its protective design is essential to enhance its structural performance under various dynamic loads. Previously carried out studies on CFST columns tried to determine how to improve their structural response under various loadings, such as axial compression, lateral impact, blast, seismic, etc. Apart from investigations on transverse impact loading, the majority of the other studies on CFST under various loads established solutions and protective measures. Therefore, this study aim is to improve the performance of CFST under transverse impact loads. The geometrical and mechanical properties, boundary conditions, impact loading and dynamic explicit analysis employed in that study. This paper proposes a novel design in terms of cross-sectional configuration and smart materials to be applied on the CFST in order to improve its performance under lateral impact loading. The proposed investigation is exclusively numerical and its results were verified with the experimental results from literature. The considered three main variables were including (1) concrete-filled double skin steel tubular – CFDST with both first sandwich layer and internal carbon steel tube filled with normal strength concrete – NSC, (2) CFDST with first sandwich layer filled with Ultra High-Performance Fiber-Reinforced Concrete – UHPFRC. a. The parameters including failure modes, maximum mid-span deflection, and residual displacements were presented.