Desenvolvimento de método para a análise quantitativa da rugosidade de substratos cerâmicos argilosos

Abstract

The diversification of materials used as substrates in Civil Construction hinders the standardization of building systems, increasing the probability of pathological manifestations. An example of this is the detachment of coatings. The variability of the surface texture, as well as the rheology of the mortar used are factors that directly influence the lack of adhesion of the coating systems. In this context, the construction industry usually analyzes its materials regarding the macrostructure, not knowing the microstructure of the surface. In this context, the present research developed a quantitative method to analyze the microstructural roughness of ceramic blocks. And as results, it points out that the constituent material and burning temperature influence the roughness and contact area of ceramic substrates. The 3D data acquisition method is more efficient than the 2D method in roughness characterization of ceramic blocks. The developed method allows precise location and detail levels for evaluation of surface roughness coefficients and facilitates the comparative analysis among different ceramic block surfaces with qualitative and quantitative data. The average roughness, as a single factor of analysis, can not be used to determine the adherence between the ceramic block substrate and the mortar, since the contact area and the rheology of the mortar will also influence this parameter. The application of the method indicated that the same material adopted as substrate can present significant variation of roughness and contact area, which will directly interfere in the adherence between the ceramic block and the cementitious matrix. After the multiscale analysis with the methods for measurement analysis of ceramic blocks it is concluded that the roughness must be analyzed with equipment that allows the measurements between 0,025µm and 0,50µm. The method for roughness determination of ceramic blocks proposed in this study, with data acquisition by 3D profilometer, is appropriate for the evaluation of the roughness of a ceramic substrate, being possible the mapping of the surface, the reproduction of the data and the classification of the roughness of the ceramic substrate.