Performance of Polypropylene Fibre Reinforced Laterite Masonry Bricks

Accessibility to energy-efficient, cost-effective, and environmentally friendly materials are among the critical challenges that the building industry faces. In addition to its high cost, concrete and cement blocks or structures production is one of the factors that cause climate change. Therefore, the building industry has to develop innovative materials that contribute to the reduction of the challenges above. Due to its availability worldwide and its environmentally friendly characteristics, earth materials appear suitable against climate change in the building industry. However, blocks produced from earth materials have low compressive and tensile strengths and low durability. Recently, many researchers focused on stabilising soil with cement, lime, fibres, Etc. Cement/lime stabilisation is neither cost-effective nor energy-efficient, while natural fibres reinforcement faces durability challenges. In this study, a laterite soil was reinforced with polypropylene fibre, a type of waste plastic. The use of these plastic wastes contributes to reducing plastic worldwide and producing low-cost and environmentally friendly building materials. The main objective of this research work is to study the performance of polypropylene reinforced laterite bricks. A hair-like polypropylene fibre was mixed with air-dried laterite soil at 0, 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, and 0.4% fibre content by weight of dry soil. The blocks and bricks made were air-dried for 14 days and tested according to EN 772-1:2011 (E). The findings on the unconfined compressive strength test, indirect splitting tensile test, compression test and initial rate of water absorption test are presented in this paper. The results indicate that the compressive strength of reinforced bricks increased by 84%, and the water absorption rate was reduced by 50% at 0.23% fibre content by weight of dry soil. These results show that polypropylene fibre can be an alternative reinforcement material to produce more durable earth blocks and bricks with improved compressive strength. It is recommended that one should mix dry laterite soil with fibre. Then add the optimum water content determined from the compaction test and mix until the mixture is homogenous before making blocks/bricks. Blocks/bricks made should be air-dried, avoiding exposition to sunlight.