Investigation on Mechanical and Durability properties of Silica Fume blended cement concrete with Coal Bottom Ash as Fine Aggregate

Concrete is the most widely used substance worldwide it consumes a large number of raw materialsand has a detrimental influence on the environment. Using leftover resources from manufacturingindustries as a concrete material lessens its need to consume natural resources and promotes safer trashdisposal. This study examined the mechanical and durability performance of concrete by substituting20%,30%,40%,50% and 60% of fine aggregates weight with Coal Bottom Ash (CBA), replacing 12.5% ofthe cement weight with Silica Fume (SF). Compressive strength, split tensile and flexural strength testwere performed for mechanical properties while sulphate attack, sorptivity and carbonation depth test wereperformed for durability performance. A sequence of 35 concrete cubes were casted, comprising a controlmix and mixes that contained CBA and SF. Workability was kept constant by adjusting the dose ofsuperplasticizer with fixed w/c ratio for the mixes containing CBA and SF to maintain the workabilityvalue achieved in the control mix. The addition of 12.5% SF and 40% CBA yielded optimal compressivestrength, while 30% CBA achieved the best split tensile and flexural strengths. Compared to the controlmix, the use of these byproducts improved resistance to sulphate attack, carbonation depth andsorptivity test.