Rolling Thin Film Oven Test and Pressure Aging Vessel Conditioning Parameters: Effect on Viscoelastic Behavior and Binder Performance Grade

Abstract

This paper presents a sensitivity analysis of two parameters applied for the rolling thin film oven test (RTFOT) and pressure aging vessel (PAV) aging on the viscoelastic behavior and performance grade of asphalt binder PG 58-22. For the RTFOT, the temperature was varied from the default temperature of 163°C to 143°C and to 183°C. For the PAV, the binder film thickness was varied from the default 3.2 mm to 1.0 and 5.0 mm. Dynamic shear rheometer (DSR) tests were run with a temperature sweep from 46°C to 82°C at a frequency of 1.59 Hz on the virgin binder, as well as on the RTFOT and RTFOT+PAV-aged samples. Bending beam rheometer (BBR) tests were carried out at −12°C, −18°C and −24°C on the RTFOT+PAV-aged samples. The effect of the mentioned conditioning parameters on | G*| and δ—as well as on the upper and lower performance grade—was investigated. Results show that the effect of RTFOT temperature on the | G*| and δ is more distinct for lower DSR temperatures. In general, the effect of a change in the RTFOT temperature on the viscoelastic parameters can be considered as small. At 46°C DSR, a change of 1°C in the RTFOT temperature shifts | G*| by 2.2% and δ by 0.08°. The PAV binder film thickness has an exponential effect on | G*| and δ. A reduced RTFOT temperature leads to reduced long-term aging after PAV. Reduced short-term aging owing to reduced production temperatures results in significantly reduced long-term aging. The effect of RTFOT temperature and PAV binder film thickness on upper and lower performance grade was found to be insignificant.