MECHANICAL AND PHYSICAL PROPERTIES OF RECYCLED AGGREGATES CONCRETE

Aggregate type - natural or recycled - governs a range of concrete properties (e.g. water absorption and workability). Knowing this, there are many recommended mixing methods for maintaining concrete workability. However, they may be not economic feasible or they may depreciate mechanical properties. In this work, four concrete mixtures were produced replacing 0, 30, 50 and 100% of natural aggregates by recycled concrete aggregates without any pre-wetting method or additional water. Instead of, the “Two-Stage Mixing Approach” mixing method was used. From the experimental tests it was possible to observe the influence of the substitution content on the workability, water absorption ability, density, voids index, compressive strength, tensile strength and modulus of elasticity. In addition, the tensile strength and elastic modulus values of recycled concrete were also compared to those obtained in the equations recommended by ABNT NBR 6118:2014 for concrete with natural aggregates. The results showed that it is possible to maintain the workability of concrete without depreciating its mechanical properties.