Title: Cyclic Crack-Slip Model for Smeared Rotating Crack Formulations
Author(s): Anca C. Ferche and Frank J. Vecchio
Publication: Structural Journal
Appears on pages(s): 219-230
Keywords: crack slip; cyclic loading; reinforced concrete; shear capacity; strength degradation
An analytical model describing crack-slip behavior, compatible with smeared crack models and suited for the finite element analysis of reinforced concrete specimens subjected to reversed cyclic loading conditions, is presented. The procedure, largely based on Walraven’s monotonic formulation, calculates slip as a function of the shear stress along the crack surface, accounting for cyclic degradation due to load reversals. The formulation is compatible with a smeared rotating-crack approach in finite element analysis procedures, and has been implemented within the algorithms of VecTor2, an in-house two-dimensional nonlinear finite element program. The model keeps track of two distinct independent cracks within one element by monitoring the change in direction of the principal stress field. A cyclic degradation law is empirically derived from tests performed on push-off specimens. Herein, verification studies undertaken on concrete shell elements and shear walls are presented, indicating the suitability of the approach for modeling the reversed cyclic response of reinforced concrete. Accounting for slip results in more accurate estimates of deformation response, energy dissipation, and failure mode.