Study of the use of expanded vermiculite in the mechanical properties of light mortars

Abstract

The search for alternative materials with the potential to benefit the properties of the mortar is growing. The use of lightweight aggregates is a possibility that generates reduction in the weight of the coating itself and tend to provide great advantages as regards the thermal and acoustic insulation. Therefore, the objective of this study is to analyze the use of expanded vermiculite in the mechanical properties of light mortars. The experimental procedure started with the characterization of the materials and the production of mortars with proportions in volume of 1: 1: 6 (cement: lime: sand) with substitutions in volume of 25, 35 and 45% of the sand for the expanded vermiculite, and in then testing the fresh state (consistency, density and water retention) and in the hardened state (density, compressive strength, modulus of elasticity and adhesive strength). The results showed that the incorporation of expanded vermiculite decreases the water / binders factor, reducing the mass density in the fresh and hardened state. Water retention decreases for substitution levels of 25 and 35% and increases to 45% substitution. The bond strength is increased, while the compressive strength and the modulus of elasticity is reduced. Therefore, the use of expanded vermiculite in coating mortars has great potential for partial replacement to the natural aggregate, for the preparation of light mortars.