Study of the Mechanical Properties and the Durability of Concrete Based on Recycled Wastes Aggregates

This work focuses on the valorization and recycling of waste materials of brick aggregates (BA) and demolition concrete aggregates (DCA) for the formulation and mechanical characterization as well as the study of the durability of concrete.Five (05) concrete formulations; a control concrete based on natural aggregates and four concrete formulations based on recycled aggregates by volume substitution of natural aggregates with rates of 25% and 50% brick waste and 50%, 75% demolition concrete waste, were studies in the fresh state to estimate the workability and the density and in the hardened state to estimate the mechanical properties and the durability of concretes: Compressive and flexural strengths, impermeability to water and the diffusion of chloride ions.The results of this experimental study show that the increase in the rate of demolition or brick aggregates wastes in substitution of natural aggregates causes a decrease in the mechanical characteristics and the durability of the concrete. Nevertheless, concrete mixes containing 50% of recycled aggregates have good mechanical resistance and good durability which are close to that of concrete based on natural aggregates. Therefore, the results obtained suggest a possible use of brick and demolition concrete wastes, as aggregates in the formulation of structural concretes.