Behaviour and design of composite walls under axial compression

Abstract

An extensive investigation on the axial behaviour of composite walls was carried out with the main aim of developing design recommendations. Firstly, in order to investigate the slenderness limit for different steel grades, an experimental programme was conducted comprising six concrete filled composite panels (CF-CPs) with four shear studs symmetrically welded on one steel plate, incorporating both mild steels, high- and ultra-high-strength steels. The second set of experiments included thirteen concrete filled composite walls (CF-CWs), in which different connector types and arrangements were utilised together with mild steels, high- and ultra-high-strength steels. In parallel with the experimental tests, numerical models were developed, involving element deletion and concrete damage properties to simulate concrete crushing. Extensive parametric study was conducted based on the validated models against the test results with detailed discussions. Innovative method (both experimentally and numerically) was adopted to separate the loads carried by exterior steel plates and the infilled concrete to assist the following design recommendations. The validity of the proposed design recommendations was demonstrated through comparisons with the present test and numerical results as well as the data collected in the literature.