An Experimental investigation on unbound mixtures containing recycled materials

Conservation of resources, preservation of the environment and the increasing problems connected with the management of landfills are the main issues which developed countries have to deal with. Nowadays, the recycling of waste materials is the most suitable method in road maintenance and rehabilitation. In this context, the present research work focuses on mechanical investigations in order to evaluate the reliability of using waste materials in unbound base and/or subbase layers. In particular C&D and RAP were selected as recycled materials and compared with traditional dense – graded aggregate base coarse. Different recycled blends containing different percentage of C&D and RAP were considered in order to evaluate the effects of the nature and quantity of demolition debris on the bearing capacity of unbound road layers. To that end, a mechanical characterization based on the evaluation of design parameters such as Resilient Modulus and CBR were performed. The experimental results showed that C&D and RAP materials are a sustainable and effective alternative to traditional aggregates for base construction.