Behaviour of the Tubular Columns Filled by Concrete Subjected to Buckling Compression
This paper deals with the possibility of using high strength concrete in steel tubular columns filled with concrete subjected to compression. The effect of concrete strength on buckling resistance of the composite columns is investigated. The behaviour of the compressed tubes filled by high strength concrete is compared with that filled by normal strength concrete. The combination of circular tubes and high-strength concrete seems to be an effective way to use high-strength concrete because of eliminating the lack of tensile strength. In the case of high-strength concrete, the tensile strength is growing, not in proportion to compressive strength, but more slowly. This means that a large increase in compressive strength is not accompanied by a corresponding increase in tensile and shear strength in comparison with normal strength concrete. The confinement of the concrete core by the steel shell leads to the prevention of shear or tension failure whereas high compressive strength can be activated. This paper includes interpretation and evaluation of the results of experimental analysis. The paper also includes the results of a numerical model which has been developed to ensure consistency of the output of the numerical calculation and the data obtained with the test specimens.