Technique for evaluating kinematics between rebar and concrete

Understanding the behavior of steel-concrete interaction is of fundamental importance to the study of reinforced concrete structures. In this paper, a technique for the development of a constitutive model for that interaction is presented. In the experimental part of the study, rebar and wedge pull-out specimens were tested. The stress and displacement in the tangential direction near the rebar interface were measured; whereas phase measurement speckle interferometry was used for accurate surface displacement measurement and crack growth detection. A fracture mechanics-based numerical simulation was then used to evaluate the normal stress at the interface using the measured crack length and crack opening displacement. This hybrid numerical-experimental technique was shown to successfully predict the measured normal stress and crack profile of the wedge splitting specimen.