High-Temperature Performance and Workability of Crumb Rubber-Modified Warm-Mix Asphalt
High-Temperature Performance and Workability of Crumb Rubber-Modified Warm-Mix Asphalt

Author: Hainian Wang

Publisher:

Published: 2020

Total Pages: 17

ISBN-13:

DOWNLOAD EBOOK

Crumb rubber produced from scrap tires has been widely applied in asphalt mixtures to improve the pavement performance. Warm-mix technology has also been employed to lower the production temperature of asphalt mixtures. The objective of this article is to investigate the effects of warm-mix additive types and crumb rubber concentration on the resistance to deformation of crumb rubber-modified (CRM) binders through the repeated creep and recovery test (RCRT), dynamic shear rheometer (DSR), and rotational viscosity test. The CRM binders with crumb rubber concentrations of 10 %, 15 %, 20 %, and 25 % were prepared first as the control binders. Then, three types of warm-mix additives, Sasobit, RH, and Advera, were added into the CRM asphalt to produce CRM warm-mix asphalt (WMA) binder. Generally, the workability of CRM asphalt can be improved with the addition of warm-mix additives. The effect of warm-mix additive on the high-temperature performance is highly dependent on the crumb rubber dosage. The RCRT results overall showed that the warm-mix additives can improve the high-temperature performance of asphalt when the crumb rubber concentration is low. However, according to the DSR test, Sasobit improved the rutting resistance of CRM asphalt, while the RH and Advera sacrificed the rutting resistance. The inconsistency between the RCRT and DSR results suggests that it may be necessary to conduct both the tests when investigating the high-temperature performance of CRM asphalt with warm-mix additives.

Advances in Frontier Research on Engineering Structures Volume 1
Advances in Frontier Research on Engineering Structures Volume 1

Author: Yang Yang

Publisher: CRC Press

Published: 2023-02-08

Total Pages: 1017

ISBN-13: 1000835421

DOWNLOAD EBOOK

Advances in Frontier Research on Engineering Structures focuses on the research of advanced structures and anti-seismic design in civil engineering. The proceedings present the most cutting-edge research directions and achievements related to civil and structural engineering. Topics covered in the proceedings include: · Engineering Structure and Seismic Resistance · Structural Mechanics Analysis · Components and Materials · Structural Seismic Design · 3D Printing Concrete · Other Related Topics The works of this proceedings will promote development of civil and structural engineering, resource sharing, flexibility and high efficiency. Thereby, promote scientific information interchange between scholars from the top universities, research centers and high-tech enterprises working all around the world.

Evaluation of Performance on Crumb-Rubber-Modified Asphalt Mixture
Evaluation of Performance on Crumb-Rubber-Modified Asphalt Mixture

Author: Yuming Dong

Publisher:

Published: 2012

Total Pages: 5

ISBN-13:

DOWNLOAD EBOOK

This paper investigates the performance of crumb-rubber-modified (CRM) asphalt mixture. Two different asphalt mixtures containing two types of asphalt binder (#90 original asphalt and CRM asphalt) were used to prepare Marshall specimens and determine optimum asphalt content. Mechanical performances of asphalt mixes were evaluated by the wheel rutting test (WRT) (dynamic stability (DS)), midpoint beam bend test (MBBT), at low temperature, and indirect tensile test (IDT), at the freezing and thawing cycle. Superpave gyratory compactor (SGC) specimens were also prepared for the modulus test. Using the simple performance test (SPT) and universal testing system (UTS), viscoelastic mechanical characteristics were evaluated by static and dynamic modulus tests. Static modulus (E) data were measured by the un-confinement uniaxial compression test according to the specification of China. Moreover, dynamic modulus (E0) data were obtained by SPT. The crumb-rubber content varies from 0, 10 %, 20 %, to 30 % at the static modulus test. Two test temperatures were selected for the dynamic modulus test. The results indicated that the CRM asphalt mixture performs better than the standard asphalt mixture on dynamic behavior, rutting resistance, cracking resistance, and moisture stability.

Characterization of Low Temperature Crack Resistance of Crumb Rubber Modified Asphalt Mixtures Using Semi-Circular Bending Tests
Characterization of Low Temperature Crack Resistance of Crumb Rubber Modified Asphalt Mixtures Using Semi-Circular Bending Tests

Author: Hainian Wang

Publisher:

Published: 2016

Total Pages: 9

ISBN-13:

DOWNLOAD EBOOK

The objective of this study was to assess the low temperature anti-cracking performance of crumb rubber modified asphalt mixtures by performing the semi-circular bending tests. The flexural tensile strength, fracture energy density, and fracture resistance were used to evaluate the rubber modified asphalt mixture's performance based on fracture mechanics J-integral concept. The semi-circular bending (SCB) tests were conducted to study the effect of crumb rubber dosage, crumb rubber size, and testing temperature on the low temperature anti-cracking performance of rubber modified asphalt mixtures. Two gradations (a dense gradation mixture and a gap-gradation mixture) were selected, and five rubber application dosages (15, 18, 20, 22, and 25 %, all by the weight of base binder) were studied in the paper. The tests were performed at temperatures of 0, -10, and -20°C. The testing results indicated that the flexural tensile strength and fracture energy density increased initially, reached to a peak point and then decreased with the increase of rubber dosage. Flexural tensile strength and fracture energy density reached its maximum value at the 20 % rubber dosage among the five rubber application dosages. The flexural tensile strength, fracture energy density, and the J-integral fracture toughness of the gap-graded rubber asphalt mixture specimens were higher than those of the dense gradation. The smaller sized particle rubber modified mixture provided a better low temperature anti-cracking performance as compared to those with bigger particle sizes. Through the comprehensive consideration of laboratory test results and field results, it was recommended that the J-integral fracture toughness should be no less than 2.8 KJ/m2 for new asphalt rubber pavement in Shannxi province.

Evaluation of Engineering Properties of Rubberized Laboratory Mixes Containing Warm Mix Additives
Evaluation of Engineering Properties of Rubberized Laboratory Mixes Containing Warm Mix Additives

Author: Chandra K. Akisetty

Publisher:

Published: 2010

Total Pages: 8

ISBN-13:

DOWNLOAD EBOOK

Warm mix asphalt (WMA) refers to technologies which allow a significant reduction of mixing and compaction temperatures of asphalt mixes. From previous studies, it is observed that warm mix additives work in different ways, either in reducing the viscosity of the asphalt binder or allowing better workability of the asphalt mix at lower temperatures through volume expansion in the binder. If the technologies of WMA are incorporated into rubberized asphalt mixes, which are generally produced and compacted at higher temperature than conventional mixes, it is possible to reduce the mixing and compaction temperatures of rubberized mixes to those of conventional mixes. This paper presents a limited study that characterizes the engineering properties of crumb rubber modifier (CRM) mixtures containing warm mix additives. Six CRM mixtures (two of control mixtures and four of warm mixtures) were prepared using two aggregate sources and two additives: Aspha-min® and Sasobit®. Evaluation of all mixtures included the following testing procedures: tensile strength ratio, asphalt pavement analyzer, resilient modulus, and resilient modulus after long-term oven aging. The results from this study showed that in general, there was no significant difference between the control and warm CRM mixtures for the properties evaluated in this study, indicating that the use of WMA technologies into CRM mixes is expected to have no negative effect on the mixture's engineering properties.

Advances in Asphalt Materials
Advances in Asphalt Materials

Author: Shin-Che Huang

Publisher: Woodhead Publishing

Published: 2015-04-08

Total Pages: 493

ISBN-13: 0081002718

DOWNLOAD EBOOK

The urgent need for infrastructure rehabilitation and maintenance has led to a rise in the levels of research into bituminous materials. Breakthroughs in sustainable and environmentally friendly bituminous materials are certain to have a significant impact on national economies and energy sustainability. This book will provide a comprehensive review on recent advances in research and technological developments in bituminous materials. Opening with an introductory chapter on asphalt materials and a section on the perspective of bituminous binder specifications, Part One covers the physiochemical characterisation and analysis of asphalt materials. Part Two reviews the range of distress (damage) mechanisms in asphalt materials, with chapters covering cracking, deformation, fatigue cracking and healing of asphalt mixtures, as well as moisture damage and the multiscale oxidative aging modelling approach for asphalt concrete. The final section of this book investigates alternative asphalt materials. Chapters within this section review such aspects as alternative binders for asphalt pavements such as bio binders and RAP, paving with asphalt emulsions and aggregate grading optimization. Provides an insight into advances and techniques for bituminous materials Comprehensively reviews the physicochemical characteristics of bituminous materials Investigate asphalt materials on the nano-scale, including how RAP/RAS materials can be recycled and how asphalt materials can self-heal and rejuvenator selection

Airfield and Highway Pavement 2013
Airfield and Highway Pavement 2013

Author: Imad L. Al-Qadi

Publisher:

Published: 2013

Total Pages: 0

ISBN-13: 9780784413005

DOWNLOAD EBOOK

The proceedings of the 2013 Airfield & Highway Pavement Conference: Sustainable and Efficient Pavements, held in Los Angeles, California, June 9-12, 2013 contains 123 peer-reviewed papers that focus on the latest developments and cutting-edge technological improvements in pavements and pavement sustainability. Topics include: advanced modeling, design, and analysis of pavements; construction and rehabilitation techniques; asphalt characterization and testing; recycling materials in pavements; pavement quality control/quality assurance; pavement sustainability and life-cycle assessment; nondestructive testing and evaluation; pavement management systems; and airfield and pavement case studies. This proceedings will be of interest to researchers, designers, project/construction managers, and contractors.