Laboratory mechanical characterisation of cold recycled mixtures produced with different RAP sources

Cold Recycled Mixtures (CRM) are composed of high amounts of Reclaimed Asphalt Pavement (RAP) together with bitumen emulsion. As additional binder, some ordinary cement is normally employed. Since RAP aggregates represents almost the entire solid structure, it is important to fully characterise Cement-Bitumen Treated Materials (CBTM) produced with different RAP materials. This work focuses the characterisation at small strain level, investigating the stiffness modulus at three testing temperatures; at the failure point, measuring the Indirect Tensile Strength; and studying the fracture behaviour, in Semi-Circular Bending Test configuration. From the results, it is possible to confirm the influence of different RAP materials, also characterised by different aggregates Nominal Maximum Size. As a consequence, a reliable RAP classification can allow a better prediction of the final CBTM mechanical properties.