Use of stockpiled asphalt and demolition debris in road construction in Norway

The Norwegian company Franzefoss Ltd has during the period 1996-2000 carried out a R&D project on recycling of heavy building and construction materials (concrete, bricks, asphalt). A central part of this project has been to investigate the potential of these materials used as unbound aggregates in base course layers. Materials from two construction sites have been used for case studies. Laboratory investigations have been performed to characterise the materials, and the laying and compaction work in the field has been monitored. A preliminary conclusion is that both crushed asphalt and crushed concrete have high potentials. From a practical point of view, it is important to note that crushed concrete and crushed asphalt must be handled differently, both before and during construction. Crushed asphalt requires heavy compaction, while concrete (and bricks) are sensitive to deterioration and must be handled with care (light weight rollers etc.). The materials have different behaviour also due-to the mechanical properties (porosity, densities etc.). Hopefully this work will contribute to the on-going work with new Norwegian design standards and specifications, and open for wider use of recycled materials, in the future.