Evaluation of the effect of concrete strength increase on buckling resistance of concrete filled tubes

Abstract

The paper deals with the behaviour of steel tubular columns filled by high-strength concrete at compression load. Attention is paid especially to the strength of the used concrete and its effect on the buckling resistance of column. Results of the experimental part of research have shown that increasing of concrete strength is efficient only to a certain extent. It was found in the experimental analysis that the use of concrete class C80/95 has only little effect on increase of buckling resistance as compared with the use of concrete class C55/67. In order to evaluate the efficiency of the concrete strength increasing, a theoretical study was carried out, the results of which are presented in this paper. The paper also discusses the possibilities of using other types of concrete (light-weight concrete or slightly reinforced concrete) with regard to their contribution to improving the bearing capacity and taking into account the production costs of the steel - concrete tubular column.