Effect of Chemical Components of Asphalt Binders on Fatigue Resistance of Binder and Asphalt Mixtures in High Reclaimed Asphalt Pavement Mixtures

Multi-scale evaluation of the rheological and mechanical properties of asphalt binder has substantial importance in understanding the binder’s micro- and macro-scale properties. This study compares the macro- and micro-scale mechanistic properties of asphalt binders. Test samples used in this study include performance grade binders (PG 64-22) from two different sources along with their modified counterparts. The modifiers include polyphosphoric acid (PPA), styrene-butadiene-styrene (SBS), a combination of SBS and PPA, and reclaimed asphalt pavement. To achieve the goal of this study, atomic force microscope technology was utilized to estimate the asphalt binder’s micro-mechanical properties (e.g., Derjaguin, Muller, Toropov modulus and deformation). On the other hand, data on the macro-scale properties—such as rutting factor (G*/sinδ), consistency and penetration—of the selected binders were analyzed and compared with the aforementioned micro-level properties. The comparative analyses indicated that the micro-mechanical properties of asphalt binders followed a linear trend with the macro-scale properties. The findings of this study are expected to help researchers and pavement professionals in modeling asphalt materials when multi-scale effects are deemed to be necessary.

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Multi-scale Evaluation of Asphalt Binders Containing Different Proportions of Reclaimed Asphalt Pavement (RAP)

10.1007/978-3-030-46455-4_179 ◽

2021 ◽

pp. 1407-1413

Author(s):

K. Lakshmi Roja ◽

Bhaskar Vajipeyajula ◽

Eyad Masad

Keyword(s):

Asphalt Pavement ◽

Asphalt Binders ◽

Reclaimed Asphalt Pavement ◽

Reclaimed Asphalt ◽

Scale Evaluation ◽

Multi Scale

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Quantitative Analysis of the Blending Degree of Virgin and RAP Binders in Recycled Asphalt Mixtures with a High RAP Content

Applied Sciences ◽

10.3390/app8122668 ◽

2018 ◽

Vol 8 (12) ◽

pp. 2668 ◽

Cited By ~ 6

Author(s):

Zhen Yang ◽

Guoyi Zhuang ◽

Xiaoshu Wei ◽

Jintao Wei ◽

Huayang Yu ◽

...

Keyword(s):

Asphalt Pavement ◽

Asphalt Mixtures ◽

Reclaimed Asphalt Pavement ◽

Structural Index ◽

Comprehensive Understanding ◽

Recycled Asphalt ◽

Reclaimed Asphalt ◽

Standard Curve ◽

Study Results ◽

Mineral Additives

Recycled asphalt mixtures (RAM), which are prepared by blending reclaimed asphalt pavement (RAP), virgin bitumen and mineral additives, provide a variety of advantages, including resource recycling, reductions in costs, and reduced negative environmental impacts. However, multiple agencies have expressed concerns about the utilization ratio of RAP; thus, a comprehensive understanding of the blending degree of virgin and RAP binders in RAM would be significantly helpful for promoting the application of RAP. This study aims to quantitatively analyze the blending degree of virgin and RAP binders in RAM with high RAP contents. Carboxyl-terminated butadiene acrylonitrile (CTBN) was utilized as a tracer to mark the virgin bitumen; in addition, Fourier transform infrared (FTIR) spectroscopy was used to develop the structural index of CTBN (ICTBN). By establishing the standard curve between ICTBN and the CTBN content, the blending degree of virgin and RAP binders at different locations within RAM can be determined quantitatively. The study results indicate that the RAP binder was completely blended with the virgin bitumen in the outer RAP layer. However, the blending degree decreased with an increase in the RAP depth, and the blending degree in the inner RAP layer was only approximately half that which was found in the case of complete blending.

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