Effect of ageing on the low temperatures cracking properties of bituminous binders: new insights from bending beam rheometer measurements

Title: Effect of ageing on the low temperatures cracking properties of bituminous binders: new insights from bending beam rheometer measurements
Author(s): V. Mouillet, J. C. Molinengo, F. Durrieu, J. P. Planche
Paper category : conference
Book title: Fifth International RILEM Conference on Reflective Cracking in Pavements
Editor(s): C. Petit, I.L. Al-Qadi and A. Millien
Print-ISBN: 2-912143-47-0
e-ISBN: 2912143764
Publisher: RILEM Publications SARL
Publication year: 2004
Pages: 351 - 358
Total Pages: 8
Nb references: 14
Language: English

Abstract: Nowadays, in order to prevent some problems associated with binder-related pavement failures, it is very important to be able to characterize performance of bituminous binders. In this perspective, new test methods and specifications have been developed to more accurately predict field behaviour of all binders, regardless of how they are manufactured. Hence, in order to predict the low temperature at which the binder reaches some limiting stiffness and becomes sensitive to thermally induced cracking, the SHRP has developed the Bending Beam Rheometer (BBR). In this study, this particular rheometer was used to explore low temperature properties evolution during ageing for two 70/100 penetration grade bitumen and various Polymer modified Bitumens (PmB) manufactured by adding different levels and natures of saturated plastomers or unsaturated elastomers to these two base bitumens. Some physical blends were then in situ cross linked through a proprietary process.The binders were tested according to the SHRP recommended protocol, i.e. before and after Rolling Thin Film Oven Test (RTFOT) and Pressure Aging Vessel (PAV) ageing claimed to simulate respectively the mixing and laying processes of asphalt concrete, and the long term in-service oxidative ageing.The ageing effect through BBR parameters (creep stiffness and m-value) was evaluated with respect to the bitumen source, the polymer content and structure. For example, it appears that the ageing leads to a weaker stress relaxation ability (decrease of m-value), which may suggest poor thermal cracking resistance. The same effect is also observed with the increase of polymer content. The oxidability of the bitumen source is also of prime importance. In conclusion, the Bending Beam Rheometer appears to be a promising tool for the evaluation of binder's performance in terms of thermal cracking.

Online publication: 2004-04-15
Publication type : full_text
Public price (Euros): 0.00