INNOVATIVE COMPOSITE COLUMNS COMPRISING THIN-WALLED COLD-FORMED STEEL PROFILES AND CONCRETE

Abstract

The demand for structures using cold-formed steel sections has increased significantly since it has been recognized as a valuable and competitive structural solution. To further extend the market share of thin-walled cold-formed steel sections (CFS) it is necessary to push the boundaries of its range of applicability. To achieve this, new synergies between different structural materials must be established. Based on an experimental investigation on the buckling behaviour of built-up columns at ambient temperature and fire situation, an exploratory investigation was conducted, aiming to study a solution to enhance the structural fire performance of cold-formed steel columns and also to develop a composite solution comprising CFS profiles and concrete. In this paper, experimental results on the buckling behaviour of built-up CFS columns at both ambient temperature and fire conditions are presented and discussed. Additionally, 8 experimental fire resistance tests were conducted on composite closed built-up CFS-concrete columns. Based on the experimental results, finite element models were developed and calibrated.