Analysis and review of concrete-filled double skin steel tubes under compression

The existing literature concerning the axial performance of concrete-filled double-skin steel tubular (CFDST) columns has been reviewed in this paper. The models in the literature for predicting the behavior of steel materials and confined concrete are summarized, and their effects of the results of finite element analysis are discussed. The applicability and accuracy of four design guidelines to predict the ultimate axial strength of CFDST columns have been assessed through this review by using an expanded database of published compression tests. Code limits in cross-sectional slenderness and material strength are reviewed. The impacts of different structural parameters on the axial behavior are reviewed and discussed. The discussion results indicate that material properties and dimensions have significant effects on the axial performance of CFDST columns. The European and Australian codes give the most reliable predictions, while American design codes give conservative predictions. Finally, recommendations for future studies are provided.