Laboratory characterization of bitumen treated full depth reclamation materials

Abstract

Because of an aging road infrastructure network, interventions to restore the pavement condition, increase the user’s riding comfort, and/or improve the road safety are very common in Canada. Since the 1970s, rehabilitation treatments as opposed to new constructions have been gaining momentum. Because of the economic crisis, increased cost of materials like virgin aggregate, binder, etc., and a strong desire to preserve effective and sustainable roadway system have fueled the popularity of recycling existing pavement as a primary option. Particularly, Cold In-place Recycling (CIR) and Full-Depth Reclamation (FDR) of asphalt pavements are promising alternatives for road rehabilitation. Although Cold Recycled bituminous Materials with bitumen-stabilized materials have been successfully applied, there are still some critical problems existing in this technology. One of the areas where much work is needed is in the understanding and the modeling of the behavior of those materials at younger age. Those two materials, mostly when treated with asphalt emulsion, have evolutive characteristics with time, which is mostly linked to their water content. The mix design for CIR and FDR materials has been mostly based on Marshall mix design procedure which is empirical that makes it difficult to use in further application. The main objective of this research project is to enhance the short term and long-term performance of Cold Recycled bituminous Materials (CRM) treated with asphalt emulsion and/or with foamed asphalt. To that end, the curing temperature of CRM was varied, and it showed that cold temperature do have a negative impact on their mechanical performances. Those performances were evaluated with different tests, including complex modulus measurement that enabled us to describe their viscoelastic behavior. Complex modulus tests were also performed at young age with different confining pressure, which showed that that the behavior is between bituminous and granular material. Finally, it was possible to define the optimum binder combination by testing different double coating combinations of emulsion and/or foam in order to increase the CRM’s performances. The results from the research will contribute to a better understanding of the mix design method based on the Superpave gyratory compactor, and rheological properties of the Cold Recycled bituminous Materials with foamed asphalt and emulsified asphalt.

Date	4 Jun 2018
Original language	American English
Awarding Institution	École de technologie supérieure
Supervisor	Alan Carter (Supervisor) & Dharamveer Singh (Co-supervisor)