Some Properties of Concrete Contains Waste Concrete as Fine Aggregate

Abstract

In this research, experimental investigations have been carried out to assess the effect of partial replacement of fine aggregate by crushed concrete passed through a sieve size of No. 4.75 mm on workability, splitting tensile strength, and compressive strength of recycled concrete at 7 and 28 days curing periods. Two sets of fine aggregate have been used, the first set containing salts in conformity with the Iraqi Standard Specifications and another set not in conformity with the Iraqi Standard Specifications. The fine aggregate is replaced with crushed concrete in various percentages ( 25%, 50%, 75%, and 100%), while 0% represents the control. Results showed that by replacing 100% of crushed concrete after 28 days of curing, the compressive strength has increased by 79% from the compressive strength of the control mix, while the splitting tensile strength has decreased, reaching 24% of the splitting tensile strength of the control mix.