Load Capacity of Concrete Slabs with Recycled Aggregates

Abstract

Large-scale concrete slabs and laboratory-sized specimens containing recycled concrete aggregate (RCA) and fractionated reclaimed asphalt pavement (FRAP) to partially-replace the coarse aggregate were tested to failure. The concrete containing recycled aggregates had lower flexural strengths than the concrete with virgin aggregates. However, the slabs cast with recycled materials had a similar flexural load capacity to the virgin aggregate concrete slabs. The results from the large-scale testing demonstrated that these recycled materials used in the concrete slabs performed better than what the standard beam strength tests predicted, and thus the thickness design of these recycled mixtures may not need to be adjusted to account for the lower flexural strength. Several reasons for this failure behavior are the combined interaction of the material’s strength, fracture properties, and elastic modulus.