The re-use of the demolished parts of buildings is considered as an important factor of conserving natural sources and minimizing its consumption, this may be taken as a good development pattern, which leads to compatibility between economical savings and an environmental and social consideration.
Development in this sense not only aims at improving production but also takes into account the abiding by the production rules in considering the available sources, its cost, and its overall effect on environmental and social values. To carry out this research work a number of concrete mixes were prepared using different ratios the specimen then tested the outcome of the crushed concrete specimens were then used as coarse aggregate to constitute new concrete mixes of similar ratios for studying the mechanical properties of those new mixes and comparing then with the original mixes.
The results indicated clearly the possibilities of using recycled destroyed concrete as aggregates also the results showed a reduction in the compressive strength and an increase in tensile strength. Finally a mix design procedure is given foe the future design of any mix using crushed recycled concrete as an aggregate.