Propriedades termomecânicas de argamassas adicionadas com bentonita e resíduo de vermiculita.

Abstract

In the face of climate change, an increase of 3°C in terrestrial temperature is expected by 2030, as a result of the rapid growth of urban areas and a poorly efficient energy plan, where buildings have important contribution to the solution, as they are responsible by the growth of global energy demand. In this context, it is necessary to develop materials that can be applied in these buildings, with the function of reducing energy consumption through improved thermal properties and preferably local materials that reduce the generation of solid waste. This work aimed to analyze the viability of bentonite and vermiculite residue in partial replacement of binder and aggregate, respectively, in coating mortar. Mortars were prepared in different substitution contents (0, 4, 8 and 12% for bentonite and 60% for vermiculite residue) that correlate, for better comparative evaluation, in addition to the reference mortar. The mortars were monitored in the resisted state by means of physical and mechanical characterization tests (resistance to compression, traction by diametral compression and water absorption by immersion and capillarity), after 28 days of curing. The microstructural analysis was performed using diffraction, X-ray fluorescence and thermogravimetry assays. The thermal behavior was evaluated by determining the conductivity, resistance and thermal transmittance of the material. The A60C4 mortar showed better results in terms of resistance to tensile strength and diametral traction, with increases of 5.45% and 78.15%, respectively, in relation to the reference mortar. Greater water absorption by immersion and capillarity in mortars containing vermiculite and bentonite residue. In thermal properties, the best results were also shown in the A60C4 mortar, with 33.3% improvement in conductivity, 57.14% in resistance and 32.25% in transmittance. The results made it possible to conclude that the A60C4 mortar was a good thermal insulator, allowing better thermal comfort for users inside the buildings coated with it.