Finite element modelling of reinforced concrete beam column joints

Abstract

To model the complex behavior of reinforced concrete analytically in its non-linear zone is difficult. This has led engineers in the past to rely heavily on empirical formulas which were derived from numerous experiments for the design of reinforced concrete structures. The Finite Element method makes it possible to take into account non-linear response. The FE method is an analytical tool which is able to model RCC or retrofitted structure and is able to calculate the non-linear behavior of the structural members is Finite element method. For structural design and assessment of reinforced concrete members, the nonlinear finite element (FE) analysis has become an important tool. The method can be used to study the behavior of reinforced and pre-stressed concrete structures including both force and stress redistribution. The Finite Element method allows complex analyses of the nonlinear response of RC structures to be carried out in a routine fashion. FEM helps in the investigation of the behavior of the structure under different loading conditions, its load deflection behavior and the cracks pattern. External wrapping with fiber-reinforced polymer (FRP) is a promising solution for retrofit of beam-column joints due advantages such as high strength-weight ratio, corrosion resistance, ease of application, low labour costs, and no significant increase in member size over other strengthening techniques. Also, recent research has attempted to simulate the behavior of reinforced concrete structures strengthened with FRP composites using the finite element method (FEM). In the present study, the non-linear response of RC beam column joint under the incremental and cyclic loading and the stressed retrofitted (90% and 75%) RC beam column joint under the cyclic loading using FE Modelling has been carried out with the intention to investigate the relative importance of several factors in the non-linear finite element analysis of RC beam column joints. These include the variation in load displacement graph, the crack patterns, propagation of the cracks, the crack width and the effect of the non-linear behavior of concrete and steel on the response of control and stressed retrofitted beam column joint.