South African Conference on Polymers in Concrete, Berg-en-Dal, Kruger National Park Jun 20-23, 2000

6. Surface Levelling

Macroroughness, Microroughness and Ultra-Microroughness
The roughness of a surface can be considered from the aspects of macroroughness (0.1…1.0 mm), microroughness (0.001…0.005 mm) and ultra-microroughness (> 0.005 mm). It is obvious that a layer of sealant 0.1 mm thick can only level microroughness and ultra-microroughness. If shot blasting or milling, for example, generate roughness in the 0.1 mm range, then a levelling filler with its associated additional costs must be applied first if the structure of the base preparation is no longer to be visible

Roughness Scale (Ultramicro 1 nm; Mikro 1µm; Makro 100 µm)

Unevenness, Holes and Joints
Every substrate must first be mechanically treated in order to remove cement skin and contamination. Shot blasting is most often used for this purpose, although the base surface is also diamond ground or milled. The criteria for the selection of the method, however, remain unclear to me. The resulting roughness varies greatly, and they are defined by ICRI in 9 profiles. Their consumption figures are given in Table 4, for a density of 1.4 kg/ltr..