Abstract
The use of sisal fibre for reinforcement in concrete slab members is developed and placed under study due to the reasons being faced in the Nigeria construction industries. Galloping inflations, lack of quality control & production of inferior materials are general challenges faced in the construction industry. This combined with low quality iron ore and high sulphur & phosphorous contents of Nigerian ore leads to production of inferior steel materials with reduced diameter or low yield strength. This leads to this study on assessing the behaviour of sisal fibres serving as steel support materials. A mix design survey was conducted by visiting in-state construction contractors to assess concrete mix grades and quantities adopted for use, which was used as a guide to mix the concrete for this study. A total of 52kg of cement, 104kg of coarse aggregate, 52kg of fine aggregate and 0.5% water cement ratio was used. An average sisal fibre percentage of 0.5% was used for this study, serving as reinforcement and steel supporting material in a 500mm × 200mm × 100mm concrete slab. A total of 12 samples were cast and cured, (3 of plain concrete, 3 of concrete and fibre reinforcement, 3 of steel reinforcement and 3 of steel and fibre reinforcement). These samples were subjected to bending test after three (3) days of curing in water to assess the flexural strength of the samples. The result showed that the sample with sisal fibre reinforcement only recorded the highest flexural strength of 3.41 N/mm2. A linear increase in flexural strength was noticed with increase in steel reinforcement to an average strength of 6.12N/mm2. The concrete produced can thus be used in every day-to-day practice.

Key words: Sisal Fiber (SF), Shear Behaviour (SB), High Strength Reinforced Concrete Slabs (HSRCS), Steel-Polypropylene (S-PP), Steel-Sisal (S-Si), Steel Fiber Reinforced Concrete (SFRC), Polypropylene Fiber Reinforced Concrete (PFRC), Sisal Fiber Reinforced Concrete (SiFRC), Sisal Fibre Reinforced Cementitous Matrix (SFRCM), Oil Palm Broom Fibre (OPBF),