Influence of the physical and chemical characteristics of sediment fillers on the properties of mastic asphalt

Abstract

This study aims to optimize the integration of dredged sediments as fillers in formulations of hydrocarbon materials such as “mastic asphalt” for sealing applications. River sediments were collected from the Hauts de France region are the following ones: Aire sur la Lys (ASL), Urban Community of Arras (ARS), European Metropolis of Lille (MEL), and Noyelles sous Lens (NSL) to identify the impact of integrating them in asphalt formulations. Pure asphalt mortars were formulated (AP1) according to the specifications. Asphalt based on limestone fillers have achieved mechanical performance set by the standards. It can be seen that MEL and NSL sediments have a limited use because of their high organic matter content and their high rate of Intergranular voids (RV), which leads to overconsumption of Bitumen. However the calcination of these sediments at 550 °C can remove the organic matter and give a better improvement in physical and mechanical performance than the quicklime treatment. Asphalt-based calcined sediment at 550 °C (NSLC) has been shown to deliver up to 80% improvements in the mechanical performance in comparison to the raw sediment mix. In addition, the use of a soft grade of Bitumen gave impressive benefits with the sediment fillers which can reach up to 23% substitution and reducing the quantity of Bitumen up to 19%.