Suitability of Crushed Palm Kernel Shells for Concrete Production

The suitability of palm kernel shell as a partial replacement of fine aggregate in concrete was researched to verify if concrete made with palm kernel shells meet some minimum standard prescribed for strength and density. Based on British standard classification of fine aggregate as aggregates passing the number 4 sieve of 4.75mm size or slightly higher sizes depending on local requirement, crushed palm kernel shells of particle diameter not greater than 5.0mm was used to replace river sand as fine aggregate in the following percentages: 0%, 10%, 20%, 30%, 40% and 50%. For each mix proportion, three concrete cubes were cast and tested for compressive strength and density at 7, 14 and 28 days curing duration. The specific gravity of all the concrete ingredients were determined and used in preparing the concrete mix proportion. Sieve analysis of the different materials was also carried out in order to grade the fine aggregates used for the research as well as to determine their fineness modulus. The crushed palm kernel shell used was obtained by grinding palm kernel shells into fine sizes using grains’ grinding machine. Afterwards, it was sieved through 5mm sieve and use for the research. Mix ratio of 1:2:4 was adopted with water-cement ratio of 0.60. The results of the research showed that, eventhough there was significant reduction in the strength of the concrete as the quantity of crushed palm kernel shell (PKS) increases, crushed palm kernel shells can be used up to 10% to replace sand in lightweight concrete production as it produced a compressive strength of 27N/mm2 against the 30N/mm2 of the control.