3. Properties of protective coating formulations

Numerous protective products can be applied to concrete surfaces (acrylic-, alkyd-, polyester-, vinyl- and epoxy-based paints, etc.) . However, the low level of microporosity and surface roughness of UHPC means that products with low viscosity and good spreading properties must be applied to form a film-forming, homogeneous coating. Indeed, UHPC surfaces have little tolerance to over-application, which can lead to aesthetic defects (e.g. "orange peel" effects). In this section, the most commonly used types of coating will be described, the majority of which are applied using compressed-air spray guns.