Unit Weight, Strengths and Thermal Conductivity of Cellular Lightweight Fly Ash Geopolymer Mortar Reinforced with Polyvinyl Alcohol

Abstract

Lightweight materials are the most popular building wall construction materials because of their fast installation, high insulation, and low cost. However, these materials use cement as a binder. Cement production releases carbon dioxide emissions resulting in environmental issues. The research investigated the use of fly ash geopolymer and polyvinyl alcohol (PVA) to enhance the mechanical and thermal properties of cellular lightweight mortar. The effects of PVA concentrations, foam content (Fc), and curing time on properties of the cellular lightweight fly ash geopolymer (CLFAG) mortar reinforced with PVA specimens were evaluated. The results revealed that the PVA concentrations and Fc had an effect on the unit weights of the CLFAG reinforced with PVA specimens. The lowest unit weight of the specimens was 10.10 kN/m 3 at a PVA concentration of 20% and Fc of 2%. According to the Thailand industrial standard for C12 and C14 CLC block types, all mixed ingredients met the unit weight and compressive strength requirements. The correlation between unit weight and thermal conductivity of CLFAG reinforced with PVA specimens was represented by a linear function, which was a useful equation for estimating the thermal conductivity of specimens.

The Precursors Used for Developing Geopolymer Composites for Circular Economy—A Review

“…Also, the ratios between the added precursors has an influence on the surface structure of the samples. To improve thermal and mechanical properties of light mortars, Tiyasangthong et al [64] have carried out some tests on cellular mortars with geopolymers based on fly ash reinforced with polyvinyl alcohol (PVA) specimens. The mortars also contained an air foaming agent and an alkaline activator based on silicate and sodium hydroxide (NaOH).…”

“…The thermal conductivity of the mortars investigated in the same study, at 7 and 28 days, decreased with increasing concentrations of PVA and foam. The authors believe that due to the larger pores that occur at a higher content in foam, thermal transport is hindered by the formation of larger PVA films [64]. The addition of MgO in the concrete composition can act as an expansion agent, because it forms Mg(OH) 2 crystals in the presence of water whose growth can reduce the risk of cracking.…”