STRENGTH PROPERTIES OF CONCRETE USING SHEANUT (VITELLARIA PARADOXA) SHELL AS PARTIAL REPLACEMENT FOR COARSE AGGREGATE

The increasing demand for conventional coarse aggregates in concrete production has led to the depletion of natural resources and a rise in environmental concerns. In view of this, an investigation into the use of sheanut (Vitellaria paradoxa) shells as partially in concrete was studied in this project with the aim of assessing its feasibility as an alternative aggregate in concrete production. Sheanut shells were collected, cleaned, dried, crushed, and sieved to conform to standard coarse aggregate sizes. Concrete samples were prepared with varying replacement levels of 0%, 10%, 20%, and 30% by weight of coarse aggregate. Physical properties determined were particle size distribution, specific gravity, and AIV. A designed mix of 1:2:2.3 for grade M15 was used, and specimens were cast, cured and tested for 7, and 28 days compressive strength. Slump test, density and water absorption tests were also carried out. Results showed that the physical properties of the concrete materials met the standard requirement for concrete production. Also, the workability reduces with increase with sheanut shell dosage, and at each replacement, all the slump is classified as very low. The maximum water absorption occurs at 7days, and this reduces as the curing age increases. The compressive strength of the cubes increases with curing age from 7 days to 28 days, while the strength reduces as the percentage of sheanut increases in the mix. Therefore, only the control mix (0%) was able to meet the designed grade of 15N/mm² at 28days, with percentage increase of 14.49%, a value of 15.41N/mm², meaning that at 10%, 20%, 30% replacement, sheanut shells cannot be used as coarse aggregate in concrete production. It was therefore recommended that the effect of lesser percentage replacement e.g. 2.5%, 5% other than 10% of sheanut used in this research should be examined, and the effect of sheanut shells on other grades of concrete should be investigated, likewise the effect of long term strength development should be researched i.e. 42days, 56days, 90days etc.