Nonlinear numerical analysis of corroded reinforced concrete structures using laminated frame elements

Abstract

This study presents an innovative numerical model built on the position-based finite element method, using laminated frame elements to predict the displacement of beams under corrosion-a common type of damage in reinforced concrete structures resulting from the penetration of chlorides and carbon dioxide. Over time, these reactions lead to detrimental effects such as cracks, reduction of rebars' area and consequently stiffness reduction. The expected increase of corrosion impact due to climate change-induced rising temperatures and heightened carbon dioxide levels highlights the crucial need to comprehend the structural behavior under corrosive conditions for precise displacement prediction and determination of maintenance intervals. The proposed model incorporates the geometric and physical non-linearity along with the uniform reduction in rebar area that subsequentially affects the elements' inertia and, therefore, the stiffness of the structure. Notably, the obtained results for beam displacements under carbonation-induced corrosion exhibit promising agreement with existing literature, validating the effectiveness of the proposed approach.