Efeito do método de mistura nas propriedades de argamassas com poliestireno expandido

Abstract

In recent decades, concepts such as energy management and efficiency are extremely important in construction building field. It is evident that the use of more sustainable materials and techniques are increasingly necessary in a world that produces more and more waste. Expanded polystyrene (EPS) is widely known and used in the construction industry due to its properties such as low density, low thermal conductivity, high capacity to absorb deformations and versatility. However, inappropriately discarded EPS often becomes an environmental problem. This is because it takes up a lot of space in both dumps and landfills and has a potential for wasted reuse. In this context, this study aims to analyze the influence of the mixing method on the properties of mortars with EPS. For this, two mixing models were proposed that alternate the addition order of mortar materials where 50% of the volume of fine aggregates are replaced by virgin and recycled EPS particles. The mixing process in cementitious composites plays a fundamental role in determining their performance. With this in mind, the analysis of the influence of the two proposed mixing processes on the properties of mortars with EPS is the main objective of this work. The consistency was kept constant for all mixtures by adjusting the dosage of superplasticizer additive. The analysis performed compared mortars with two types of EPS and two mixing methods regarding their physical and mechanical properties. Tests were carried out to verify consistency, density and water retention in the fresh state. At 28 days, tests were carried out on compression, dynamic modulus of elasticity, bending tension, specific mass and void index. The mixing methods proved to be effective against segregation problems and had little influence on the properties evaluated in relation to the type of EPS. In general, mortars with recycled EPS performed better than virgin pearls ones. Mortars with expanded polystyrene showed greater capacity to absorb deformations, but it was not possible to see the influence of the type of mixture on water retention, modulus of elasticity and void ratio. The results showed that mortars with EPS lose mechanical performance in relation to the reference, but still have adequate properties to be used in coating walls and ceilings, mainly.