Experimental Study On The Effects Of Replacement Of Cement By Silica Fume Admixture And Pumice

Abstract

The aim of the project work is to study the behavior of conventional aggregate concrete replaced with pumice aggregates in volume percentages of 0%, 20%, 40%, 60%, 80% and 100% and cement replaced with the silica fume in weight percentages of 0%, 5%, 8%, 10%, 15% and 20%. The conventional mix has been designed for M20 grade concrete. In this investigation cubes, cylinders, beams and slabs of standard size have been cast and tested after 28days of curing period. Three specimens have been cast for each variable and thus totally 540 specimens are tested. With 20% pumice stone in the normal coarse aggregate  and cement replaced with silica fume in weight percentages of 0%, 5%, 8%, 10%, 15% and 20%, compressive strength, split tensile strength, flexural strength and moment carrying capacity of concrete specimens increase upto 5% of silica fume and then decrease. With 40% pumice stone in the normal coarse aggregate  and cement replaced with silica fume in weight percentages of 0%, 5%, 8%, 10%, 15% and 20%, compressive strength, split tensile strength, flexural strength and moment carrying capacity of concrete specimens increase upto 8% of silica fume and then decrease. With 60% pumice stone in the normal coarse aggregate  and cement replaced with silica fume in weight percentages of 0%, 5%, 8%, 10%, 15% and 20%, compressive strength, split tensile strength, flexural strength and moment carrying capacity of concrete specimens increase upto 8% of silica fume and then decrease. With 80% pumice stone in the normal coarse aggregate  and cement replaced with silica fume in weight percentages of 0%, 5%, 8%, 10%, 15% and 20%, compressive strength, split tensile strength, flexural strength and moment carrying capacity of concrete specimens increase upto 8% of silica fume and then decrease. With 100% pumice stone in the normal coarse aggregate  and cement replaced with silica fume in weight percentages of 0%, 5%, 8%, 10%, 15% and 20%, compressive strength, split tensile strength, flexural strength and moment carrying capacity of concrete specimens increase up to 10% of silica fume and then decrease.