Abstract: In this research replacement of cement with silica fume which is finer than cement yields higher strength and durability to the concrete structure. Steel fibers are used to enhance strength properties and ductility of concrete. The coarse aggregate replaced partially with the demolished waste aggregate of 50%. Cement with silica fume added in different percentages of 5, 10, 15 and 20%. Strength tests are conducted at 7 and 28 days for hardened concrete to evaluate the strength such as compressive and spilt tensile. The partial replacements of 10-15% of combined use of silica fume and fly ash allowed increasing the strength parameters.

Keywords: compressive strength, demolished waste aggregate, silica fume, split tensile strength test.

| DOI: 10.17148/IARJSET.2021.8747