COMPARATIVE ANALYSIS OF CONCRETE PRODUCED WITH DIFFERENT POZZOLANS

Abstract

The study compared the strength of three different pozzolanic concrete- Rice Husk Ash (RHA), Powdered Burnt Brick (PBB) and Saw Dust Ash (SDA)) in ordinary water at 84 days. This was achieved by partially replacing Ordinary Portland Cement (OPC) with 10 percent (%) of each pozzolan to produce three different pozzolanic concrete cubes. Control Samples of 100% OPC were equally produced. Absolute volume method of mix proportioning was adopted using a mix ratio of 1: 2: 4. Water-cement (w/c) ratio of 0.65 was also adopted for all the specimens. Nine (9) concrete cubes were produced for each specimen. The specimens were completely immersed in ordinary water for 28, 56 and 84 days respectively, during which three (3) cubes from each specimen were removed and tested to determine their compressive strengths at every curing period. The strengths of RHA, PBB, SDA and the control specimens in ordinary water at 84 days were observed to be 28.25N/mm2, 28.20N/mm2, 22.80N/mm2 and 31.60N/mm2 respectively. The study concluded that OPC/ RHA and OPC/PBB concretes perform better than OPC/SDA at 84 days in ordinary water. The research recommended that RHA and PBB could be used for load bearing concrete structures.