The Applicability of Estimated Equations of Recycling Agents on the Viscosity Variety of Aged Asphalt Binders

2013 ◽  
Vol 723 ◽  
pp. 670-677 ◽  
Author(s):  
Ping Sien Lin ◽  
Chi Wen Chang ◽  
Tung Lin Wu

This study was to perform the viscosity test of adding different ratios (from 10% to 40%) of three recycling agents (RAs), namely RA25, RA75 and RA250, to the reclaimed asphalt binder (RAB) containing a viscosity of 42800 poises. The purpose of the study was to determine the effects of various RAs on the viscosity of aged asphalt binders. The viscosity values were also estimated based on the recycling model of aged asphalt binder developed by authors and the equations developed by Arrhenius (1887), Grunberg and Nissan (1949) and Epps et al. (1980). The results show that there are significant variations in the viscosity of recycling asphalt binder when being added different ratios of RA. The estimated viscosity values computed by the recycling model of aged asphalt binder are closer to the tested results when compared with the equations developed by Arrhenius (1887), Grunberg and Nissan (1949) and Epps et al. (1980). Furthermore, the Recycling Index (RI) developed by the recycling model of aged asphalt binder can clearly and precisely reveal the recycling performance of different kinds of RAs. The Gmix from the equation developed by Grunberg and Nissan (1949) has an apparent effect on estimating the viscosity when adding RA to the RAB.

2017 ◽  
Vol 737 ◽  
pp. 547-553
Author(s):  
Iva Krcmova ◽  
Petr Hyzl ◽  
Pavla Nekulova ◽  
Pavel Coufalik ◽  
Ondrej Dasek

With increased demand and limited aggregate and binder supply, hot mix asphalt (HMA) producers discovered that reclaimed asphalt pavement (RAP) is a valuable component in HMA. This paper is concerned with the current issue of higher using RAP (Reclaimed Asphalt Pavement) in asphalt mixtures for pavement wearing courses. It describes the effects of application of three types of rejuvenation additives on properties of aged asphalt binders made from a regular RAP. These rejuvenation additives restore the physical and chemical properties of aged binders. In addition, the aged asphalt binder with rejuvenators applied was subjected to a short-term laboratory aging using the RTFOT (Rolling Thin Film Oven Test). This method simulate aging asphalt binder during the manufacturing process and laying. To assess the binder properties, both the standard empirical tests and more advanced functional tests (dynamic shear rheometer and bending beam rheometer) have been performed. Last part of the paper provides an evaluation of the individual rejuvenation additives. Based on the results it can be concluded that a positive change in properties of aged asphalt binder after applying all the three rejuvenators has been proven.


2017 ◽  
Vol 863 ◽  
pp. 129-134
Author(s):  
Petr Hyzl ◽  
Iva Krcmova ◽  
Pavla Nekulova ◽  
Ondrej Dasek ◽  
Pavel Coufalik

Recycling asphalt pavement creates a cycle of reusing materials that optimizes the use of natural resources. Reclaimed asphalt pavement (RAP) is a useful alternative to virgin materials because it reduces the need to use virgin aggregate. This paper is concerned with the current issue of using RAP in Stone Mastic Asphalt (SMA). SMA is a wearing course, which is especially stable and durable. It describes the effects of application of rejuvenators on properties of asphalt binders. These rejuvenation additives restore the physical and chemical properties of aged binders. In addition, the aged asphalt binder with rejuvenators applied was subjected to a short-term laboratory aging using the RTFOT (Rolling Thin Film Oven Test). To assess the binder properties, both the standard empirical tests and more advanced functional tests (dynamic shear rheometer and bending beam rheometer) have been performed. Last part of the paper provides an evaluation of the individual rejuvenation additives. Based on the results it can be concluded that a positive change in properties of aged asphalt binder obtained from a modified RAP (from SMA) after applying all the rejuvenators has been proven. The effect of the rejuvenators during the manufacturing process and laying has been verified.


2020 ◽  
Vol 17 (2) ◽  
pp. 1040-1043 ◽  
Author(s):  
Nur Shahira Samsuri ◽  
Norhidayah Abdul Hassan ◽  
Nurul Hidayah Mohd Kamaruddin ◽  
Mohd Rosli Hainin ◽  
Mohd Ezree Abdullah ◽  
...  

This research examines the impacts of adding various source and percentages of waste engine oil (WEO) on the physical and rheological characteristics of asphalt binder comprising aged asphalt binder. A base asphalt binder with penetration grade of 80/100 and aged binder were blended with three sources of WEO at 0%, 5%, 10%, 15%, and 20% by the weight of asphalt binder. These oils were collected from light vehicle (motorcycle), heavy vehicle (lorry), and heavy machinery (tractor). Penetration and softening point procedures were done to define the physical properties of the unmodified and modified asphalt binders. Meanwhile, the rheological property was evaluated with a dynamic shear rheometer (DSR). The results show that the high percentages of WEO increased the penetration and decreased the softening point. The addition of 15% and 20% of WEO especially from heavy machinery reduced the rutting resistance. Therefore, it is recommended that the modification of aged binder with these types of WEO should be up to 10%.


2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Mojtaba Mohammadafzali ◽  
Hesham Ali ◽  
James A. Musselman ◽  
Gregory A. Sholar ◽  
Aidin Massahi

Fatigue cracking is an important concern when a high percentage of Reclaimed Asphalt Pavement (RAP) is used in an asphalt mixture. The aging of the asphalt binder reduces its ductility and makes the pavement more susceptible to cracking. Rejuvenators are often added to high-RAP mixtures to enhance their performance. The aging of a rejuvenated binder is different from virgin asphalt. Therefore, the effect of aging on a recycled asphalt mixture can be different from its effect on a new one. This study evaluated the cracking resistance of 100% recycled asphalt binders and mixtures and investigated the effect of aging on this performance parameter. The cracking resistance of the binder samples was tested by a Bending Beam Rheometer. An accelerated pavement weathering system was used to age the asphalt mixtures and their cracking resistance was evaluated by the Texas Overlay Test. The results from binder and mixture tests mutually indicated that rejuvenated asphalt has a significantly better cracking resistance than virgin asphalt. Rejuvenated mixtures generally aged more rapidly, and the rate of aging was different for different rejuvenators.


Author(s):  
Ramez Hajj ◽  
Angelo Filonzi ◽  
Syeda Rahman ◽  
Amit Bhasin

The low-temperature properties of asphalt binder have attracted attention in recent years thanks to an increase in the use of reclaimed asphalt pavements (RAP). Traditional methods to evaluate the low-temperature properties of the binder require a large amount of binder that needs to be recovered from RAP samples for testing with a Bending Beam Rheometer (BBR). To economize on sample size for RAP materials and also for emulsion residues, previous researchers have explored the potential of using a 4 mm diameter specimen with a Dynamic Shear Rheometer (DSR) in lieu of the BBR. To compare results from frequency sweep tests conducted using the DSR with results from the BBR, data from the former need to be converted to time domain and subsequently from a shear load response to an axial load response. Previous research studies have developed methods to accomplish these two conversions to compare data from the DSR with data from the BBR. The objective of this study is to examine some of these methods from the literature and elsewhere based on the principles of linear viscoelastic interconversion using a set of 11 different binders. Results using different analytical approaches from this study show that the DSR has good repeatability and verify that it can be used as a surrogate for the BBR to determine low-temperature properties, while exercising some caution with some of the assumptions related to Poisson’s ratio.


Author(s):  
Peyman Barghabany ◽  
Wei Cao ◽  
Louay N. Mohammad ◽  
Samuel B. Cooper ◽  
Samuel B. Cooper

Because of limited amounts of natural resources, reclaimed asphalt pavement (RAP) has gained popularity in the asphalt pavement industry to meet sustainability requirements in asphalt pavement. Concerns have been raised in relation to the intermediate temperature cracking performance of asphalt mixtures containing RAP. The objective of this study was to evaluate the intermediate temperature cracking resistance of asphalt mixtures and recovered asphalt binders containing RAP. Seven plant-produced asphalt mixtures from three transportation agencies with various RAP contents and the extracted asphalt binders were evaluated with respect to intermediate temperature cracking resistance. Asphalt binder experiments included chemical and rheological characterization of recovered asphalt binders. Chemical characterization consisted of Fourier transform infrared spectroscopy and saturates/aromatics/resins/asphaltenes component analysis. Linear amplitude sweep and time sweep tests were also performed to characterize the rheological properties of asphalt binders. Asphalt mixture experiments included four-point bending beam fatigue and semi-circular bend tests. Results indicated that, as expected, asphalt mixtures with high RAP contents resulted in asphalt binders and mixtures with reduced cracking resistance. Relationships between the asphalt binder chemical and rheological parameters and asphalt mixture cracking resistance were also investigated. Asphalt binder rheological and chemical parameters were well correlated. Asphalt binder rheological parameters showed reasonable to strong relationships with the four-point bending beam fatigue test result. The work presented in this paper is part of FHWA Transportation Pooled Fund Project TPF-5(294) “Develop Mix Design and Analysis Procedure for Asphalt Mixtures Containing High RAP and/or RAS Contents.”


2021 ◽  
Vol 11 (12) ◽  
pp. 5698
Author(s):  
Jian Zhou ◽  
Jing Li ◽  
Guoqiang Liu ◽  
Tao Yang ◽  
Yongli Zhao

Increasing the content of reclaimed asphalt pavement material (RAP) in hot-mix recycled asphalt mixture (RHMA) with a satisfactory performance has been a hot topic in recent years. In this study, the performances of Trinidad lake asphalt (TLA), virgin asphalt binder, and aged asphalt binder were first compared, and then the modification mechanism of TLA on virgin asphalt and aged asphalt was explored. Furthermore, the RHMA was designed in accordance with the French norm NF P 98-140 containing 50% and 100% RAP, and their high-temperature stability, low-temperature cracking resistance, and fatigue performances were tested to be compared with the conventional dense gradation AC-20 asphalt mixture. The results show that the addition of TLA changes the component proportion of virgin asphalt binder, but no new functional groups are produced. The hard asphalt binder modified by TLA has a better rutting resistance, while the fatigue and cracking resistance is lower, compared to both aged and virgin asphalt. The high-modulus design concept of RHMA is a promising way to increase the RAP content in RHMA with acceptable performance. Generally, the RHMA with 50% RAP has similar properties to AC-20. And, when the RAP content reaches 100%, the high- and low-temperature performance and anti-fatigue performance of RHMA are better than AC-20 mixture. Thus, recycling aged asphalt using hard asphalt binder for hot-mixing recycled asphalt mixture to increase the RAP content is feasible.


Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7080
Author(s):  
Xiaorui Zhang ◽  
Chao Han ◽  
Xinxing Zhou ◽  
Frédéric Otto ◽  
Fan Zhang

Soybean-derived bio-oil is one of the vegetable-based oils that is gaining the most interest for potential use in the rejuvenation of aged asphalt binders. This laboratory study was conducted to characterize and quantify the diffusion and rheological properties of bio-oil-rejuvenated aged asphalt binder (BRAA) using soybean oil. In the study, the chemical structure of the soybean oil was comparatively characterized using an element analyzer (EA), gel permeation chromatography (GPC), and a Fourier infrared (FTIR) spectrometer, respectively. Based on the chemical structure of the bio-oil, BRAA molecular models were built for computing the diffusion parameters using molecular dynamic simulations. Likewise, a dynamic shear rheometer (DSR) test device was used for measuring and quantifying the rheological properties of the aged asphalt binder rejuvenated with 0%, 1%, 2%, 3%, 4%, and 5% soybean oil, respectively. The laboratory test results indicate that bio-oil could potentially improve the diffusion coefficients and phase angle of the aged asphalt binder. Similarly, the corresponding decrease in the complex shear modulus has a positive effect on the low-temperature properties of BRAA. For a bio-oil dosage 4.0%, the diffusion coefficients of the BRAA components are 1.52 × 10−8, 1.33 × 10−8, 3.47 × 10−8, 4.82 × 10−8 and 3.92 × 10−8, respectively. Similarly, the corresponding reduction in the complex shear modulus from 1.27 × 107 Pa to 4.0 × 105 Pa suggests an improvement in the low-temperature properties of BRAA. Overall, the study contributes to the literature on the potential use of soybean-derived bio-oil as a rejuvenator of aged asphalt binders.


2021 ◽  
Vol 13 (19) ◽  
pp. 10938
Author(s):  
Nathanyawat Sedthayutthaphong ◽  
Peerapong Jitsangiam ◽  
Hamid Nikraz ◽  
Suriyavut Pra-ai ◽  
Sarintip Tantanee ◽  
...  

The application of asphalt hot mix recycling is one challenge in sustainable road pavement research. In addition to the vast amount of research on the performance of recycled asphalt–concrete, the research on the frictional resistance of recycled hot mix asphalt is still limited. The effects of aged asphalt and aged aggregates on the skid resistance of recycled hot mix asphalt were investigated in this research. The aged asphalt and aged aggregates were carefully extracted from the field-reclaimed asphalt pavement, and the engineering and mechanical properties of aged and virgin aggregates were measured. The degradation of recycled hot mix asphalt was simulated using an accelerated polishing machine to mimic road surface abrasion. Accordingly, the initial and final skid resistances of the recycled hot mix asphalt were determined and correlated with the properties of the aged asphalt and aggregates. The initial skid resistance of recycled hot mix asphalt decreased with reductions in penetration and ductility of the blended asphalt. However, the changes in the blended asphalt properties contributed only small variations to the final skid resistances of the recycled hot mix asphalt. The gradations of recycled hot mix asphalt correlated only with the final skid resistances. The aggregate gradations controlled the characteristics of the final skid resistance since the covered binder was partially polished off from the road surface at this stage.


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