Comparative study of different numerical methodologies for the ciclic behavior of RC members: experimental validation

Abstract

This work mainly aims at a comparative study between several numerical methods for non-linear cyclic behavior simulation of reinforced concrete members, namely the continuum damage, the fiber and the concentrated plastic hinge models, in order to establish the applicability of each numerical tool. The damage model is based on 2D or 3D finite element representations, adopting two scalar damage variables for the simulation of non-linear concrete degradation mechanisms under tension and compression, and using the well known Giuffré-Menegotto-Pinto model to simulate the cyclic behavior of steel. The well known fiber model, computationally lighter than the previous one, resorts to 1D constitutive laws for both concrete and steel to simulate the non-linearity of fibers. Finally, the lightest model herein considered is the concentrated plastic hinge model: it is essentially a global element model for RC members, such that each is represented by an elastic central zone plus two finite-length plastic end-zones where non-linear behavior is simulated through cross-section level Takeda type moment-curvature global laws. The study was performed using these methodologies for simulating tests carried out at the Laboratory of Earthquake and Structural Engineering of the Faculty of Engineering of University of Porto (LESE - FEUP) regarding two types of elements, viz building solid columns and hollow-section bridge piers. The analyses allowed assessing each methodology advantages/limitations in simulating the cyclic behavior of the referred elements for different failure situations, particularly emphasizing those where shear failure is observed.