Surface properties of concrete and criteria for adhesion of repair systems

Before any repair operation, an effective assessment of the concrete substrate has to be performed. Usually next to the surface reparation of concrete, evaluation of the cohesion of the superficial concrete is requested for adhesion and durability reasons. Many authors describe the influence of the surface preparation technique on the superficial cohesion of concrete or the adhesion. However, the real effects of surface preparation technique only begin to be investigated in terms of superficial microcracking or roughness quantification.
This project was performed in regards to the influence of concrete substrate strength and preparation technique efficiency. The effect of the concrete removal/preparation technique is most likely dependent upon the nature and the quality of the concrete substrate. Preparation techniques are compared from the point of view of concrete removing but also potential deterioration. The visual observation of the concrete surfaces indicates that the high pressure water jetting technique induces a particular texture characterized by large waves mostly parallel to the water flow. The concrete slabs have afterwards been covered with a Self-Compacting Repair Mortar and adhesion has been characterized.