Experimental-Numerical Analysis of the Effect of Bar Diameter on Bond in Pull-Out Test

Abstract

Bar diameter is one of the basic factors affecting bond behavior, which is still of interest due to opposing opinions regarding its effect on bond behavior in the pull-out test. This paper presents an experimental and numerical bond analysis of ribbed reinforcing bar in concrete. The aim was to experimentally evaluate the effect of bar diameter on the bond behavior in the pull-out test and to perform numerical simulations of the conducted experiments in ABAQUS to verify their convergence to the obtained experimental results. The experiments used concrete of C35/45 grade and B500SP reinforcing steel bars of three diameters: 10, 12, and 16 mm. FEA simulations employed the Concrete Damaged Plasticity (CDP) material model and the Contact Cohesive Behavior (CCB) method to model the concrete–bar interface. The study shows that bar diameter significantly affects the bond, both on the bond stress–slip relationship and the type of bond failure, as well as on the bond strength. FEA simulations correctly reflected the bond behavior observed in the specimens. The analytical models presented estimates that were too conservative regarding the maximum bond stress relative to the experimental results.