Confinement evaluation of concrete-filled box-shaped steel columns

다국어 초록 (Multilingual Abstract)

This paper presents a three-dimensional finite element analysis methodology for a quantitative

evaluation of confinement in concrete-filled box-shaped unstiffened steel columns. The confinement effects

of concrete in non-circular sections can be assessed in terms of maximum average lateral pressure. A brief

review of a previous method adopted for the same purpose is also presented. The previous method is based on

a two-dimensional finite element analysis method involving a concrete-steel interaction model. In both the

present and previous methods, average lateral pressure on concrete is computed by means of the interaction

forces present at the concrete-steel interface. Subsequently, the strength enhancement of confined concrete is

empirically related to the maximum average lateral pressure. The results of the former and latter methods are

then compared. It is found that the results of both methods are compatible in terms of confined concrete

strengths, although the interaction model yields a somewhat overestimated estimation of confinement than

those of the present method when relatively high strength concrete is used. Furthermore, the confinement in

rectangular-shaped sections is investigated and the reliability of previously adopted simplifications in such

cases is discussed.