Performance Analysis of Spinifex Fibre-Reinforced Mudbrick as a Sustainable Construction Material for Remote Housing in Australia

As a sustainable construction material, mudbrick can be used widely in areas where common modern construction materials are not easily accessible but high clay content soil is available. The inclusion of locally available natural fibres in mudbrick could improve its mechanical and erosion resistance performance. This study examines the performance of fibre-reinforced mudbrick from spinifex and laterite soil which are abundant in Australia. The main objective of this study is to evaluate the mechanical and durability performance of spinifex fibre-reinforced mudbricks made with Australian laterite soil, focusing on the influence of fibre content, fibre length, and cement stabilisation. Spinifex fibre length (30 mm, 40 mm, 50 mm), spinifex fibre percentage (0.3%, 0.6%, 0.9%), and cement percentage (5% and 10%) are considered as the experiment variables. Results show that compressive strength generally decreases with fibre size. In this regard, specimens with 0.3% spinifex fibre, 40 mm fibre length, and 10% cement, with an average compressive strength value of 4.1 MPa, were found to have the highest strength among all design mixes. The elastic Young’s modulus was highest for the specimens with 0.3% spinifex fibre, 30 mm fibre length, and 10% cement with a 36.1 MPa. A low amount of longer fibres was found to be more effective in reducing water absorption in samples with higher cement content. Water absorption and compressive strength results suggest that, on average, 0.3–0.5% spinifex content of size 30 mm improves both low and high cement content mudbricks properties.