Évaluation de l'effet d'ajout du régénérant sur le bitume vieilli et sur les enrobés recyclés à froid

Abstract

The aging of bitumen presents one of the biggest problems in the recycling of bituminous mixtures. It leads to the change in the chemical structure of the bitumen, an increase in its viscosity and rigidity. The use of rejuvenators is one of the solutions proposed to reactivate the existing aged bitumen in recycled aggregates, mainly to retrieve its initial properties and consequently increase the percentage of recycled pavement rehabilitation. The present research consists of evaluating the effect of the addition of a rejuvenator, primarily on the rheological properties of the aged bitumen and secondly on the mechanical properties of the cold asphalt mixtures. To do this, three blends of the aged bitumen extracted from a GBR, aged bitumen with the addition of the 10% of the rejuvenator (Slop Wax) and the bitumen extracted from a mixture of MR-5 with regenerated emulsion after fifteen days of the cure have been tested. BBR and DSR tests were carried out on the three mixtures to determine their high (Te) and low (Tb) temperatures. FTIR spectrometry tests used to see the influence of the rejuvenator on the chemical structure were also carried out. Then, tests of complex modules and rutting were carried out on MR-5 cold-recycled mixtures with and without the addition of the rejuvenator. The results show that the addition of the 10% of a rejuvenator to the aged bitumen makes it possible to decrease the high temperature and the low temperature of the bitumen, analysis of the results of FTIR spectrometry shows that after the addition of the rejuvenator, Intensity of the oxidation spikes C = O and S = O is decreased. The addition of a rejuvenator leads to a reduction in the complex modulus E* of the cold-recycled asphalt as well as its resistance to rutting. This can be explained by the reduction in the viscosity of the aged bitumen and a partial correction of the maltene - asphaltene ratio. It is then important to evaluate the influence of the curing period on the interaction between the aged bitumen, the addition bitumen and the regenerating bitumen and possibly to try other types of rejuvenator and other percentages.

Date	2 Mar 2017
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Alan Carter (Supervisor) & Daniel Perraton (Co-supervisor)