This study explore the possibility of using waste ground palm kernel (GPK) shells as partial replacement of cement in concrete using mechanical destructive method has been studied. The palm kernel shells were in two forms: the GPK ordinary shells and shells subjected to incomplete combustion (i.e. the GPK “fuel” shells. In the preparation of the concrete specimens the mix ratio was 1: 2: 4 (cement: sand: stone) by weight and The replacement percentage was 0%, 20%, 30%, 40%, 50% and 60% respectively.  Concrete specimen were molded in both cubic and cylindrical form and its impact on the mechanical properties such as workability, compressive strength and flexural strength using destructive test method were studied. The cubic specimen were tested at 7, 28 and 60 days whiles the cylindrical specimen were tested at 7 and 28 days. Results of physical and chemical analyses suggest that GPK “fuel” shells have acceptable cementitious properties whiles GPK ordinary shells does not. Generally, the compressive and flexural strengths of concrete containing GPK shells decrease as the replacement percentage increases. However, the values of these properties increase as the period of curing increases. The optimum level of GPK shells replacement is 20% for the ordinary shells and 30% for the “fuel” shells considering compressive strength at 28 days for the cubic samples. For the flexural strength on the cylindrical specimen, up to 60% replacement of cement by GPK shells cured for 28 days has acceptable flexural strength. In spite of the findings that the GPK ordinary shells do not have cementitious properties, the mechanical properties on such concretes can be used in low strength constructions as pavements, walk ways and non structural domestic work at a lower cost than using cement.

The objective of this research is to investigate the utilization of palm kernel shells in ground form (GPK) for partial replacement of ordinary Portland cement (OPC) in concrete by investigating its optimal strength using nondestructive ultrasonic pulse velocity method for both cubic and cylindrical concrete test specimen. In all a total of 135 cubes and 66 cylinders of concrete were prepared. The dimension of the cubic concrete specimens was 150 × 150 × 150 mm and that of the cylindrical specimens were 110 mm and 500 mm diameter and length respectively. The mix design of the GPK shells used as a partial replacement for OPC ranged between 0% and 50% by weight of cement using mix ratio of 1:2:4 with water to cement ratio of 0.8. The concrete specimens were test at curing periods of 7 days, 28 days and 60 days for the cubes and 7 days and 28 days for the cylinders.  Based on the results and the analysis done, it was generally observed in all cases that, as the mix ratio is increased, the ultrasonic pulse velocity, modulus of elasticity and the density decreased and as the curing period increased, these values increased across all the mix ratios. The ultrasonic pulse velocity and the density of the specimens shows that concretes containing GPK “fuel” shells has higher values than those containing GPK ordinary shells. Generally, the density, ultrasonic pulse velocity and the modulus of elasticity of concrete containing GPK shells decrease as the replacement percentage increase.