Behaviour and failure modes of steel parking structure column under transverse impact

Abstract

The columns of steel parking structures are prone to collision while parking vehicles. The current design codes offer limited guidance for designing built-in columns with sufficient impact resistance to transverse impacts. In this study, we performed a series of numerical studies to comprehensively understand the behaviour and failure modes of the impacted column. First, a simplified analysis method was proposed to simplify the overall structural model. The simplified analysis models (SAMs) and overall analysis models (OAMs) were compared, and the results demonstrated that the proposed method can reasonably predict the behaviour of the impacted column. The behaviour of the column was estimated under common loading conditions, and the effects of the impact velocity, axial loading, and impact height were studied. Furthermore, two structural configurations, SAM-1 and SAM-2, were compared and evaluated. SAM-2 had better impact resistance than SAM-1 owing to the presence of a back beam, which reduced the effect of the additional moment due to deformation, thereby decreasing the external work and total input energy. The failure modes were classified into three categories considering different impact velocities, axial loads, and impact heights. The robustness of the structure under impact can be improved by designing a reasonable axial loading level for the column to avoid failure mode 3.