Investigation of physical, chemical and rheological properties of bituminous binders modified with different rejuvenators

Abstract

Due to the increase in the demand for hot mix asphalt, natural materials are decreasing recently, and the use of recycled asphalt (RAP) in the highway sector comes to the fore. However, the bituminous binder in RAP ages significantly due to long periods of exposure to atmospheric effects. Therefore, the researchers focused on effective restoration of RAP properties by adding adequate rejuvenates. However, although the use of these rejuvenates offers several advantages, they could also lead to some problems that could limit highway applications. One of these problems is the difference between the chemical composition and colloidal structure of rejuvenated bitumen and pure bitumen and the resulting impact on long-term performance of the reclaimed asphalt mixture. Thus, nonage hardened bitumen was used in the study to analyze the negative effect. In the present study, 5 different rates of two rejuvenates (SYLVAROAD ™ RP1000 [R1] and ITERLENE ACF 2000 GREEN [R2]) with different viscosities were applied to non-aged binders. Penetration, softening point, elastic recovery, flash point, force ductility, Brookfield viscosity and dynamic shear rheometer (DSR) tests were conducted to analyze the physical and mechanical properties of bituminous binders. As the additive content increased, complex modulus values decreased with both types of additives. According to the results of the Fourier transform infrared spectroscopy experiment, it was determined that the rheological and physical properties of the bitumen prepared with two rejuvenators had an effect similar to those of pure binder.