Investigating the interaction between asphalt binder and fresh and simulated RAP aggregate

Abstract

Although the role of individual ingredients of hot mix asphalt (HMA) such as asphalt binder and aggregates on its performance is readily recognized, there is only limited understanding about the interactions between these components and the properties of binder-aggregate interface. In order to study the interactions between asphalt binder and mineral aggregates, an interfacial test method was developed and its effectiveness was evaluated. Interfacial interactions were evaluated by testing thin films of an asphalt binder interfaced with the surface of aggregates under two different modes of loading in shear: sinusoidal oscillation and monotonically increasing. An Interaction Parameter (IP) was proposed to quantify the binder-aggregate interfacial effects. The results show that the methodology used in this study can quantify the effects of interaction between the asphalt binder and mineral aggregates. Furthermore, this research also investigated the interaction of an asphalt binder with the surface of simulated reclaimed asphalt pavement (RAP) aggregates. The results from this research not only provide an insight to the effects of binder-aggregate interaction, but can also help practitioners to better understand the effect of mixing conditions on the properties of mixtures produced using different materials.

Electrically-conductive asphalt mastic: Temperature dependence and heating efficiency

“…In dry mixing method, all 19 the components including the conductive filler are mixed at a temperature range of 150-160°C 20 [7], [27], and in wet mixing method, the conductive fillers are first blended with bitumen at an 21 elevated temperature range of 170-180°C [29], [30], and then the modified bitumen is mixed 22 with other components. Increasing the mixing temperature increases the oxidation of bitumen 23 [31]; as a result, to reduce the bitumen oxidation, dry mixing method was utilized in this study, and using a rotational viscometer -and following the ASTM D4402 standard [32] -the 1 minimum mixing temperature of PG 58-28 was determined as 145°C. It was attempted to mix 2 the mastic components at 145°C, but the conductive fillers -especially CFs at high dosage rates, 3 e.g., 2.5% -were not distributed evenly in the mastic.…”

Recycled stone mastic asphalt mixtures incorporating high rates of waste materials

“…Thus, all the SMA mixtures studied have reduced sensitivity to water. This good performance of all SMA mixtures can be partially associated with the use of limestone filler, which improves the adhesion between asphalt binders and aggregates, reducing their water sensitivity [28,29]. The SMA recycled asphalt mixtures produced with the bitumens modified with EO and polymers, namely SMA-REO15H6, SMA-REO15S5 and SMA-REO15R20, present the higher TSR values, respectively 95%, 101% and 98%.…”

Effect of Recycling Agents on Rheological and Micromechanical Properties of SBS‐Modified Asphalt Binders

“…However, these were mainly done through indoor aging tests, and many factors affecting asphalt aging remain to be studied further, such as influence mechanism of water on asphalt aging, the relationship, and the difference between simulated and natural aging. erefore, we also need to further study the asphalt aging performance and mechanism using advanced modern analytical test methods and various aging test methods to provide a theoretical basis for asphalt pavement recycling [1][2][3][4][5][6][7]. Zhang et al studied the three types of aging methods on the performance of SBS-(styrene-butadiene-styrene-) modified asphalt, including thin film oven test (TFOT), pressure aging vessel (PAV), and ultraviolet (UV) radiation.…”