Improvement of Gypsum Behaviour Using Glass Wool

Abstract

This paper presents an experimental investigation to assess the behaviour of gypsum plasters containing glass wool. Two types of locally available gypsum powder Gypsum-1 and Gypsum-2 were used in this study. The addition of glass wool was done as a partial replacement by volume at five different ratios 5%, 10%, 15, 20% and 25%. A comprehensive experimental programme was designed to measure both mechanical and thermal characteristics using 122 samples with different size configuration. These include tests for setting time, compressive and flexural strengths, density at ambient and high temperatures, thermal conductivity and thermal resistance. In order to explore actual behaviour, the test results have been compared with relevant BS EN and Iraqi Standards. The results obtained showed that both compressive and flexural strengths have consistent behaviour for all of the tested samples. The highest values of compressive and flexural strengths were 4.17 MPa and 2.11 MPa for modified gypsum mixtures of Gypsum-2 containing 20% and 25% glass wool respectively. The added amount of glass wool in addition to its distribution within the samples are the most critical parameters governing overall mechanical behaviour. The control gypsum mixtures of both Gypsum-1 and Gypsum-2 exhibited cracks at high temperatures, whereas modified mixtures seem to be durable at these conditions. Some improvements have been obtained in terms of thermal conductivity and thermal resistance for the modified gypsum mixtures.