Equilibrium moisture content of earth bricks biocomposites stabilized with cement and gypsum

Abstract

In recent years, energy efficient and ecologically friendly buildings have been important in the housing and construction sector. One of the major barriers to producing good and useful products is the lack of detailed information about natural materials, in particular their moisture related properties, as these materials are hygroscopic and sensitive to moisture. This research aimed to determine the equilibrium moisture content of earth block materials, as an extremely important characteristic variable for all physical simulations. Earth bricks with different compositions were fabricated from cohesive soil, cement, and gypsum combined with two kinds of natural fibers. Wheat and barley straw were used as reinforcing fibers and materials were treated at various temperatures (10–40°C) and relative humidity (33–95%). The moisture content was considered in dynamic equilibrium with the environmental conditions and the effects of relative humidity and temperature were investigated. The effect of relative humidity was observed more pronounced than that of temperature. The test results are discussed with reference to the relevance of the earth bricks as an ecologically friendly building material that is directly associated with the moisture related properties of buildings. The results also showed significant improvement in the durability.