Determination of the bearing capacity of encentrally compressed concrete filled steel tubular columns on the basis of the deformation theory of concrete plasticity

Abstract

Objective. The article proposes a method for finite element analysis of pipe-concrete columns in a physically nonlinear setting by reducing a three-dimensional problem to a twodimensional one based on the hypothesis of plane sections.Method.The equations of the theory of plasticity of concrete by G.A. Geniev are used. The technique was tested by comparing the solution with a calculation in a three-dimensional setting in the LIRA-SAPR software package, as well as with the experimental data of A.I. Sagadatov and calculation according to the current Russian design codes for steel-pipe concrete structures.Result. It has been established that the effective area of operation of columns with a circular cross section is small eccentricities of the longitudinal force.Conclusion. The proposed approach can be applied to the analysis of the stress-strain state and the bearing capacity of pipe-concrete columns of arbitrary section. There are no restrictions on the composition of concrete, and the shell material can be not only steel, but also fiberglass.

Keywords

• concrete filled steel tubular columns
• finite element method
• dilatation
• theory of plasticity
• physical nonlinearity