A state-of-the-art review on roughness quantification methods for concrete surfaces

Surface roughness plays an important role in the behavior of concrete-to-concrete interfaces. Methods like sand-blasting and hydrodemolition are usually adopted to improve the surface roughness of the concrete substrate. Before placing the new concrete layer it is common to verify the roughness level by visual inspection. However, this procedure can lead to inaccurate conclusions since it is influenced by the technician’s opinion and, therefore, it is subjective. Current design codes of concrete structures implicitly propose this type of assessment since there is not a specified method or device to verify the conditions of the substrate surface. To overcome the drawbacks of this qualitative methodology, a quantitative approach should be adopted instead. Thus, it is necessary to measure the surface roughness and, from this, to compute roughness parameters. This paper presents a review on roughness quantification methods that can be adopted for concrete surfaces.