Adhesive anchors in high performance concrete

Experiments were performed to evaluate the mechanical response of adhesive anchors embedded in high performance concrete (HPC). The variables include compressive strength of the concrete, addition of steel microfibers, load direction, embedment depth and edge distance of anchors. These two latter parameters influence the results both in terms of strength and ductility, while fibers strongly affect only the post-peak behavior and the failure pattern. The influence of the selected factors on the results, in terms of strength, stiffness, failure mode and failure pattern, is discussed. Finally, by considering tensile test results, an approach to evaluate the true bond strength is proposed. Shear test results are compared with standard equations to determine their suitability in predicting the behavior in HPC. The results showed that fiber reinforced concrete is a practical alternative when edge distance, short anchor spacing or thin depth member is required. In addition, it seems that unconfined tests in HPC allow to better evaluate the bond strength of the bonding agent.