Strength and deformation property enhancement of compressed steel tube-concrete elements using super concrete and thin-shell structure

Abstract

The article analyzes the changes in the strength and deformation property of compressed steel tube-concrete elements when the quality indicators of the original concrete (strength class for axial compression) and the metal shell are changed. The methodology of testing for central compression of steel tube – concrete columns with a core of ordinary and super concrete with a thin-shell structure is described. Comparative dependences of the relative deformations in the axial and circumferential directions depending on the relative loading levels, destructive load values for samples from ordinary and super concrete are presented. According to the results of the research, it was determined that with an increase in the class of concrete, the efficiency ratio of the concrete is reduced by an average of 12%, however, the increase in bearing capacity remains quite noticeable. In addition, the use of high-strength concrete class C80 increases the deformability by about 10% compared with concrete class C40 steel-concrete columns, with significant savings in metal.

Simplified 2D Finite Element Model for Calculation of the Bearing Capacity of Eccentrically Compressed Concrete-Filled Steel Tubular Columns

“…Krishan and A.I. Sagadatov [31][32][33]. The compa experimental data for two series of columns with an outer diameter of the of 159 and 219 mm and wall thickness of 6 and 8 mm, can be introduced re Also, the developed methodology and software was tested on experimental data presented in the works of A.L.…”

“…Krishan and A.I. Sagadatov [31][32][33]. The comparison with the experimental data for two series of columns with an outer diameter of the concrete core of 159 and 219 mm and wall thickness of 6 and 8 mm, can be introduced respectively.…”

Simplified Method for Calculating the Bearing Capacity of Slender Concrete-Filled Steel Tubular Columns

“…An important feature of such structures, in comparison with traditional reinforced concrete elements, is their increase in bearing capacity due to the action of concrete in triaxial compression [5]. In addition, due to the clip effect, CFST columns are characterized by a plastic fracture pattern, even when high-strength concretes are used [6]. In addition to these factors, concrete-filled steel tubular columns have a number of significant advantages, including savings on formwork, the possibility of mounting the frame in the winter period, etc.…”