Concrete Based on Recycled Aggregates for Their Use in Construction: Case of Goma (DRC)

The following study is aimed at valorizing an important part of waste from building demolition, particularly concrete as a source of aggregates for their usage in new hydraulic concrete formulation. The experimental study mainly consisted of physical characterization of natural and recycled aggregates respectively and the impact of the latter on some properties of the new formulated concrete, actually their respective consistencies for fresh concrete and mechanical strength for the hardened one. The outcome of the study shows that the recycled aggregates are more heterogeneous and have a high capacity of water absorption, but which still respects the current standards of concrete. The need for additional water has been observed for recycled aggregates-based concrete so as to have the same workability. About the compressive strength, mechanical properties obviously show that, at 28 days from setting up, concretes from recycled aggregates can reach compressive strengths range between 20 and 25 MPa without any sophisticated technology. So, these results show that we can efficiently contribute to the protection of environment by valorizing waste from concrete-based building demolition on the one hand; and the preservation of natural reserve on the other. And both advantages contribute to sustainable development overall goals.