Behaviour of concrete-filled hollow structural steel (HSS) columns with pre-load on the steel tubes

Abstract

The use of hollow structural steel (HSS) columns filled with concrete has become widespread in the past few decades. However, these members are susceptible to the effects of pre-load on the steel tubes during construction. Nineteen concrete-filled HSS columns with the steel tubes subjected to pre-load have been tested. An attempt to predict the load–deformation behaviour of concrete-filled HSS columns with the steel tubes subjected to pre-load is proposed in this paper. A comparison of the results calculated using this model shows good agreement with the test results. The theoretical model, and the influence of the pre-load ratio, slenderness ratio, steel ratio, as well as the strength of the materials are discussed. Finally, formulas for the calculation of the ultimate strength of concrete-filled steel tubular columns with the steel tubes subjected to pre-load are developed; such formulas should be suitable for incorporation into building codes.