Study on Bond-slip Behavior between Non-uniformly Corroded Reinforcement and Concrete

Abstract

In order to improve the stress concentration in concrete at steel nodes caused by zero thickness springs, the improved Spring2 nonlinear spring model from ABAQUS is used to simulate the bond-slip behavior between non-uniformly corroded reinforcement and concrete. Based on the collected test results with different stirrup spacing, fitting the influence coefficients of bond stress under stirrup corrosion. With the combination of a non-uniformly corroded rebar distribution model, the refined numerical simulation of the drawing process of reinforced concrete specimens was carried out using ABAQUS. The study shows that the improved nonlinear spring model is better than the zero thickness spring model in terms of computational accuracy and efficiency. The stirrup correction coefficient is approximately linear with the stirrup spacing; the bond-slip relationship considering the effect of stirrup spacing, has a better consistency with the relevant tests in the simulation of the pullout test. Weibull distribution for the fitting of non-uniform corrosion of reinforcement is more reasonable than Gumbel distribution.