Keywords : Cement
journal of kerbala university,
2014, Volume 10, Issue 2, Pages 11-24
This research is deliberate the effect of using recycled coarse aggregate from wasted concrete as a substitute for natural coarse aggregate with different ratios 0%, 20% , 40% , 60% , 80% and 100% study the fresh and hard concrete properties (slump , compressive , tensile , absorption , density ) and the effect of adding super plasticizer with 2% ,3% by weight of cement on above properties mixtures. Results show the negative effect on concrete properties when replacing natural coarse aggregate with recycled coarse aggregate. That effect was little when used 20% percentase replacing and increasing when percent replacing increasing . Results show improvement recycled coarse aggregate concrete with addition 2%,3% super plasticizer in mixture and manufacturing new concrete with 80% recycled coarse aggregate and 3% super plasticizer with same properties natural coarse aggregate concrete .