Constitutive models for fibre reinforced soil bricks

In this paper, the physical, durability and mechanical properties of soil bricks reinforced with chicken feather fibres (CFF) and sugarcane bagasse fibres (SBF) were studied. The adopted optimum lengths of 15-mm of CFF and SBF were randomly distributed in the soil mix at 1%, 3%, 5%, 7%, 9% and 11% by weight. In total, 525 samples of cubic (3 5 0) and prismatic (1 7 5) soil samples were prepared for each fibre type and tested in accordance with the guidance in the British standards for bulk density, water absorption, compressive strength and tensile strength at 14, 28, 56, 90 and 180 days. With the addition of 7% CFF and 5% SBF, soil brick samples were found to be 98.8% and 78.7% stronger respectively in compression compared to the control mix. Based on the experimental results the stress-strain model describing the soil bricks response to compressive loading for each fibre type was obtained via regression analysis. This study contributes original data to the characterization of soil bricks and provides reference values that can be considered for design purposes. The soil bricks thus developed will contribute to the provision of affordable and sustainable housing construction across the world, particularly in developing countries.