Adaptive Finite Elements for Reinforced Concrete Framed Structures

Abstract. This work focuses on the modelling of nonlinear response of reinforced concrete structures by means of the finite element method. A new technique which employs a variable mesh in order to reduce the computational cost of classical approaches is presented. For some piecewise linear constitutive models which are widely employed for the modelling of reinforced concrete, some properties of the solution can be predicted. The knowledge of these properties can be used as a discretization criterion of the structural elements. Therefore, the nonlinearity of the problem is easily handled with an iterative scheme that modifies adaptively the position of the nodes. The results obtained on some framed structures show that with this scheme we obtain accurate solutions with a substancial reduction of the computational cost compared with the solutions obtained with fixed meshes, both for loading and unloading states.