Stiffness of cold asphalt mixtures with recycled aggregates from construction and demolition waste

The stiffness of cold asphalt mixtures (CAM) with 100% recycled construction and demolition waste aggregates (CDWA) was studied from three different points of view: the indirect tensile stiffness modulus (ITSM), the dynamic modulus at different temperatures and frequencies and the correlation between them. It was found that CAM with CDWA frequently achieved higher stiffness than control mixes using natural aggregate (NA), but that they required significantly higher bitumen and water contents. They were less temperature susceptible, therefore potentially more fatigue resistant, but more complicated to design. Finally, a clear dependency on the compaction process (static and gyratory) was also found.