Buildings (Mar 2023)

Expanded Vermiculite: A Short Review about Its Production, Characteristics, and Effects on the Properties of Lightweight Mortars

  • Plínio Campos de Assis Neto,
  • Leane Priscilla Bonfim Sales,
  • Palloma Karolayne Santos Oliveira,
  • Iranilza Costa da Silva,
  • Ilana Maria da Silva Barros,
  • Aline Figueiredo da Nóbrega,
  • Arnaldo Manoel Pereira Carneiro

DOI
https://doi.org/10.3390/buildings13030823
Journal volume & issue
Vol. 13, no. 3
p. 823

Abstract

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Global temperatures have led to an increasing need for air conditioning systems. So, because of this fact, buildings have been improved in terms of their thermal and energy efficiency. Regarding this, the Brazilian standard ABNT NBR 15.575-4/2013 set minimum parameters for the thermal transmittance and thermal capacity of sealing elements, which allow classifying the thermal efficiency of the building. In order to comply with the requirements, the usage and study of lightweight construction materials have been in focus. An example of these materials is vermiculite. The present research reviewed articles about expanded vermiculite. The study involved the examination and comparison of various articles to analyze the properties of vermiculite and the impact of its usage on coating mortars. It was possible to verify that using vermiculite in mortars caused bad workability and a decrease in mechanical strength. However, the porosity and water absorption in mortars increased. Additionally, it reduced the specific weight and the thermal conductivity of the mortars, allowing for a better thermal insulation of the rooms. As an alternative to decreasing the negative effects of vermiculite, it is possible to use chemical admixtures, mineral additions, and mix design with a greater consumption of binder or a combination of particle sizes.

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