Study on high strength concrete using polypropylene fiber and pumice aggregate

This study evaluated replacement of normal coarse aggregates by pumice aggregates and including polypropylene fibers in percentages on the mechanical performances of M40 concrete, such concrete would achieve the strength for High Strength. The experimental program comprised an in-depth mix design for M40 concrete, nominal mixes, and other combinations of pumice and polypropylene fiber. Pumice aggregates were used as replacement levels of 25%, 30%, 35%, 40%, and 45%, with concomitant use: 0%, 0.25%, 0.50%, 0.75%, and 1% of polypropylene fiber added. A total of 5 concrete cubes mixtures were prepared, for each fiber-pumice combination. The compressive strength test on the concrete specimens determined fiber-pumice strength characteristics. The results illustrated a decline in compressive strength with increasing pumice content, especially at the higher replacement levels. Concrete with pumice replacement of 25% to 30% and added fiber of 0.25% to 0.5% would give satisfactory results for High Strength Concrete. Further increase in pumice content decreased concrete density, favouring lightweight construction applications. However, compressive strength varies concerning replacement ratio and fiber content. Inclusion of polypropylene fibers increased tensile strength and crack resistance of the concrete.