Rheology of Crumb Rubber-Modified Warm Mix Asphalt (WMA)

This study explores the impact of adding waste vehicular crumb rubber to the commercially available warm mix additives Sasobit<sup>®</sup> and Zycotherm<sup>®</sup> on modified asphalt binders’ physical and rheological properties. Various concentrations of crumb rubber (0%, 1...

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Main Authors: Ghazi G. Al-Khateeb, Alaa Sukkari, Helal Ezzat, Eyad Nasr, Waleed Zeiada
Format: Article
Language:English
Published: MDPI AG 2024-03-01
Series:Polymers
Subjects:
Online Access:https://www.mdpi.com/2073-4360/16/7/906
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author Ghazi G. Al-Khateeb
Alaa Sukkari
Helal Ezzat
Eyad Nasr
Waleed Zeiada
author_facet Ghazi G. Al-Khateeb
Alaa Sukkari
Helal Ezzat
Eyad Nasr
Waleed Zeiada
author_sort Ghazi G. Al-Khateeb
collection DOAJ
description This study explores the impact of adding waste vehicular crumb rubber to the commercially available warm mix additives Sasobit<sup>®</sup> and Zycotherm<sup>®</sup> on modified asphalt binders’ physical and rheological properties. Various concentrations of crumb rubber (0%, 10%, 15%, and 20%) were introduced to asphalt binder samples with 2% and 4% Sasobit and 1.5% and 3% Zycotherm. The investigation employed conventional tests (penetration and softening point) and advanced mechanical characterization tests, including Superpave rotational viscosity (RV), Dynamic Shear Rheometer (DSR), DSR multi-stress creep recovery (MSCR), DSR linear amplitude sweep (LAS), and Bending Beam Rheometer (BBR). Traditional tests measured the asphalt consistency, while workability was assessed through the RV test. The results showed that the Zycotherm binders experienced a more significant penetration reduction than the Sasobit binders. Additionally, an increased crumb rubber content consistently elevated the softening point and rotational viscosity, enhancing the complex shear modulus (G*) values. Rubberized binders exhibited an improved rutting performance and low-temperature PG grades. Increasing the crumb rubber content enhanced fatigue life, with Z1.5CR20 and S2CR20 demonstrating the longest fatigue lives among the Zycotherm and Sasobit binders, respectively. Overall, Z1.5CR20 is recommended for colder climates, while S2CR20 is suitable for hot-climate applications based on extensive analysis.
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spelling doaj.art-53c023ec324e498cb26e4c41e0ba2e8a2024-04-12T13:25:04ZengMDPI AGPolymers2073-43602024-03-0116790610.3390/polym16070906Rheology of Crumb Rubber-Modified Warm Mix Asphalt (WMA)Ghazi G. Al-Khateeb0Alaa Sukkari1Helal Ezzat2Eyad Nasr3Waleed Zeiada4Department of Civil and Environmental Engineering, College of Engineering, University of Sharjah, Sharjah 27272, United Arab EmiratesDepartment of Civil and Environmental Engineering, College of Engineering, University of Sharjah, Sharjah 27272, United Arab EmiratesResearch Institute of Sciences and Engineering, University of Sharjah, Sharjah 27272, United Arab EmiratesDepartment of Civil and Environmental Engineering, College of Engineering, University of Sharjah, Sharjah 27272, United Arab EmiratesDepartment of Civil and Environmental Engineering, College of Engineering, University of Sharjah, Sharjah 27272, United Arab EmiratesThis study explores the impact of adding waste vehicular crumb rubber to the commercially available warm mix additives Sasobit<sup>®</sup> and Zycotherm<sup>®</sup> on modified asphalt binders’ physical and rheological properties. Various concentrations of crumb rubber (0%, 10%, 15%, and 20%) were introduced to asphalt binder samples with 2% and 4% Sasobit and 1.5% and 3% Zycotherm. The investigation employed conventional tests (penetration and softening point) and advanced mechanical characterization tests, including Superpave rotational viscosity (RV), Dynamic Shear Rheometer (DSR), DSR multi-stress creep recovery (MSCR), DSR linear amplitude sweep (LAS), and Bending Beam Rheometer (BBR). Traditional tests measured the asphalt consistency, while workability was assessed through the RV test. The results showed that the Zycotherm binders experienced a more significant penetration reduction than the Sasobit binders. Additionally, an increased crumb rubber content consistently elevated the softening point and rotational viscosity, enhancing the complex shear modulus (G*) values. Rubberized binders exhibited an improved rutting performance and low-temperature PG grades. Increasing the crumb rubber content enhanced fatigue life, with Z1.5CR20 and S2CR20 demonstrating the longest fatigue lives among the Zycotherm and Sasobit binders, respectively. Overall, Z1.5CR20 is recommended for colder climates, while S2CR20 is suitable for hot-climate applications based on extensive analysis.https://www.mdpi.com/2073-4360/16/7/906WMArheologycrumb rubbersasobitzycothermDynamic Shear Rheometer
spellingShingle Ghazi G. Al-Khateeb
Alaa Sukkari
Helal Ezzat
Eyad Nasr
Waleed Zeiada
Rheology of Crumb Rubber-Modified Warm Mix Asphalt (WMA)
Polymers
WMA
rheology
crumb rubber
sasobit
zycotherm
Dynamic Shear Rheometer
title Rheology of Crumb Rubber-Modified Warm Mix Asphalt (WMA)
title_full Rheology of Crumb Rubber-Modified Warm Mix Asphalt (WMA)
title_fullStr Rheology of Crumb Rubber-Modified Warm Mix Asphalt (WMA)
title_full_unstemmed Rheology of Crumb Rubber-Modified Warm Mix Asphalt (WMA)
title_short Rheology of Crumb Rubber-Modified Warm Mix Asphalt (WMA)
title_sort rheology of crumb rubber modified warm mix asphalt wma
topic WMA
rheology
crumb rubber
sasobit
zycotherm
Dynamic Shear Rheometer
url https://www.mdpi.com/2073-4360/16/7/906
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AT eyadnasr rheologyofcrumbrubbermodifiedwarmmixasphaltwma
AT waleedzeiada rheologyofcrumbrubbermodifiedwarmmixasphaltwma