Column–joint assembly in RC columns strengthened by steel caging

The strengthening of reinforced concrete columns by steel cages is one of various techniques available to increase ultimate column loads. Different researchers have shown the importance of the beam–column joint on the behaviour of columns strengthened by steel cages. This paper presents a parametric study using finite element models carried out with the aim of analysing the influence of the beam–column joint on the behaviour of axially loaded reinforced concrete columns strengthened by this technique. A design rule is proposed to provide a means of estimating the ultimate load capacity of column–joint assembly and recommendations are given concerning the design of the steel cage.