Nonlinear Cyclic Analysis of Reinforced Concrete Frames, Utilizing New Joint Element

In this article, a numerical model based on the layer approach is introduced for nonlinear cyclic analysis of two-dimensional reinforced concrete frames. The advantage of the proposed analytical procedure is that it takes the bond-slip, shear-slip and pull-out e ects and, also, shears deformation in the joints into account. Bar and concrete stress-strain relations, the bond stress-slip relation and the shear stress-strain relation and, also, their cyclic behaviors are adopted as known speci cations. In the modeling, each frame is divided into two types of joint element and beam-column element. The e ect of bond-slip has been considered in the formulation of a beam-column element by replacing the perfect bond assumption from the ber analysis method. Joint elements are formulated upon major behaviors including the pull-out of embedded longitudinal bars, shear and exural deformation of joint panels and shear slip in interface sections between joints and neighboring elements. The reliability of the method has been assessed through a comparison of numerical and experimental results for a variety of specimens tested under cyclic loading. A good agreement between experimental and analytical results is obtained for both cases of strength and sti ness during the analysis. Keywords: Nonlinear analysis; RC frames; Bond-slip; Joint element; Pull-out e ect