Modelling the Relationship of the Flexural Rigidity Factor and Reinforcement Ratio by Numerical Simulation

The propagation of cracks along the span of the reinforced concrete structures results in a reduction of structural stiffness. The Indonesia National Code SNI 2847-2002, which refers to the ACI 318M-2008, mandates the reduction of this moment of inertia by 35%. This reduction-number is generalized for all the reinforcement ratios. As a consequence, this will lead to a deviation in actual behaviour, since a dissimilar reinforcement ratio will result in a different stiffness modulus of the section under consideration. A non-linear Finite Element Model (FEM) based on the anisotropic material approach, is currently being developed to generate the relationship of the flexural rigidity factor as a function of the reinforcement ratio.