RTFOT BASED ON EQUIVISCOSITY WORKABILITY TEMPERATURE FOR WARM ASPHALT BINDER

Simulation of short term aging with Rolling Thin Film Oven Test (RTFOT) is a widely used practice in asphalt binder characterization for predicting under controlled laboratory conditions its response to plant mixing and paving operations. With both Warm and High Viscosity Asphalt binders the plant mixing temperature and field work condition are not generally the same as for traditional binders and, consequently, the RTFOT standard temperature (163°C), could not have correlation with the asphalt mix bitumen performance, i.e. with its durability. The main purpose of this research project is the evaluation of a RTFOT procedure, associated with the tested binder viscosity, that justifies the appropriate lab conditions to simulate the effective short term aging during mixing and compaction. In particular a Warm Asphalt binder, compared with a traditional one, were tested using the Dynamic Shear Rheometer (AASHTO T315 and EN 14770) and EN 13302 (Brookfield test) before and after short term aging with RTFOT (UNI EN 12607-1) at different temperatures. The evaluation of the rheological and physical properties of binder and respective mixes, affected by aging procedure, were conducted in order to validate the suggested test conditions.