Flexural Strength and Compressive Strength Relations of Hospital Waste Ash-Concrete

This research work was on the evaluation of the flexural strength and compressive strength relationship of hospital waste ash (HWA)-concrete. The establishment of the relationship was carried out using concrete mix of 1: 1.61: 2.5, a cement content of 420 kg/m3, and water-cement ratio of 0.52.This was used to cast beams of dimensions, 150 mm x 150 mm x 500 mm, and cured for 90 days in a water curing tank under the laboratory conditions. The HWA was used to replace cement by wt. % in the proportions of 0% to 40%. The evaluations on the statistical characteristics of the flexural strength data results showed that the addition of HWA to concrete improved the hydration process. This was reflected in the strength development of the concrete, and the strong correlation and level of significance observed with the variables (Mix and Age). The values of the MOR obtained are in the ranged of 2.1 kN/m2 (psi) and 4.0 kN/m2. This was at the optimum replacement of 20%. At this level the value of the flexural strength was approximately 19% of the compressive strength.. The two models chosen that represented the flexural strength and compressive strength relations are the square root and two-third models. The relative predictive error (RPE) for each is 0.01.