Failure Modes in Adhesive Mortars: Competition between Cavitation and Fracture Revealed by Probe Tack Test

Abstract In this study, we employ both theoretical and experimental approach to investigate the mechanisms of separation and rupture during a tensile test of materials confined between two parallel plates, utilizing the probe tack test. This study involves two materials selected for their distinct rheological behaviors: silicone oil, which exhibits Newtonian rheological behavior, and an adhesive mortar, which demonstrates Herschel-Bulkley rheological behavior. The study on the silicone oil highlighted the mechanisms of rupture cavitations’, fingering, and fracture typical of Newtonian liquids. We describe the sequence of these mechanisms and interpret the different parts of the traction curve for this material. For the Herschel-Bulkley material, we initially examined its rheological behavior and the impact of organic additives additions on its intrinsic rheological parameters, followed by an investigation of its failure mechanisms. This study enabled us to observe various types of ruptures in these materials, which exhibited characteristics that were neither purely adhesive nor cohesive.