Análise da influência de diferentes superfícies de concreto frente a resistência de aderência de uma argamassa de revestimento

Abstract

In recent years, the civil construction sector has made great progress on the construction site, using products with great technological evolution. As a consequence of this, there was an increase in the strengths obtained with concrete, to usual strengths. Likewise, the forms used for concrete started to have a smoother surface, harming the mortar's anchorage to the substrate, due to the low porosity of the concrete and little surface texture. In this line of thought, this research aims to evaluate whether the different types of concrete surfaces promote a change in the performance of the mortar coating system and identify if there is a difference between mortar coating systems with and without the use of roughcast. For this purpose, tensile adhesion tests were carried out on different types of surfaces, with different reliefs, with and without the application of roughcast and with a single concrete type, to analyze the effect of using textured formwork in concreting. Six types of surface textures were used, where the results obtained with and without roughcast of the mortar coating system were compared. The molds used were: OSB sheets, raw wood, coin format, bubble wrap, metallic and naval sheet used for a concrete of 30 MPa. Concrete and mortar characterization tests were carried out. After 28 days of concreting, the mortar coatings were applied. Subsequently, the mortar coating tensile adhesion test and the cracking follow-up were carried out. Good results were obtained for both coating systems, all of which can be applied. In general, the coating system applied over the roughcast showed better results in terms of adhesion. The coating systems with the surface left by the bubble wrap showed similar values with and without roughcast. [resumo fornecido pelo autor]