Multilevel Analysis of the Aging Mechanisms and Performance Evolution of Rubber-Modified Asphalt

Taking SBS and rubber powder as modifier, adopting the dosage of 4%, 5%, and 6% of SBS while 2%, 4%, 6% of rubber powder to prepare composite modified asphalt, studied the preparation technology of composite modified asphalt, analyzed the trend of ductility, penetration, softening point and elastic recovery. The results show a certain SBS dosage, with the increase of the rubber powder, ductility decrease while softening point and elastic recovery increase, penetration decrease first and then rise. It can provide reference for the preparation technology and performance study of composite modified asphalt.

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Management emphasis and performance in the airline industry: an exploratory multilevel analysis

Transportation Research Part E Logistics and Transportation Review ◽

10.1016/j.tre.2004.08.004 ◽

2004 ◽

Vol 40 (6) ◽

pp. 443-463 ◽

Cited By ~ 9

Author(s):

Sveinn Vidar Gudmundsson

Keyword(s):

Multilevel Analysis ◽

Airline Industry ◽

And Performance

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Workability and Performance of Polymer-modified Asphalt Aggregate Mixtures in Cold Regions

International Journal of Pavement Engineering ◽

10.1080/1029843031000097535 ◽

2003 ◽

Vol 4 (1) ◽

pp. 25-36 ◽

Cited By ~ 10

Author(s):

Hannele K. Zubeck ◽

Lutfi Raad† ◽

Stephan Saboundjian‡ ◽

George Minassian¶ ◽

P.E. John Ryer§

Keyword(s):

Cold Regions ◽

Modified Asphalt ◽

Polymer Modified Asphalt ◽

And Performance

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A Multilevel Analysis of Effort, Practice, and Performance: Effects; of Ability, Conscientiousness, and Goal Orientation.

Journal of Applied Psychology ◽

10.1037/0021-9010.89.2.231 ◽

2004 ◽

Vol 89 (2) ◽

pp. 231-247 ◽

Cited By ~ 189

Author(s):

Gillian B. Yeo ◽

Andrew Neal

Keyword(s):

Goal Orientation ◽

Multilevel Analysis ◽

Performance Effects ◽

And Performance

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Evaluation of Crumb Rubber Modification on Specification Compliance of Asphalt Mixtures

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198119834556 ◽

2019 ◽

Vol 2673 (3) ◽

pp. 540-550

Author(s):

Samuel Cooper ◽

Saman Salari ◽

David Mata

Keyword(s):

Crumb Rubber ◽

Asphalt Cement ◽

Modified Asphalt ◽

Open Graded Friction Course ◽

Cracking Performance ◽

Asphalt Content ◽

And Performance ◽

Styrene Butadiene ◽

The Impact ◽

Rubber Modification

Since 2008, the Louisiana Department of Transportation and Development (LaDOTD) has allowed the use of crumb rubber modification (CRM) as per the specifications. However, the introduction of CRM has presented unique challenges during design and production. LaDOTD districts have reported early cracking for dense-graded mixtures. Adhesion and stability issues have been reported for open-graded friction course (OGFC) and stone matrix asphalt (SMA) mixtures. Currently, LaDOTD specifications allow the contractor to switch asphalt cement supplies without redesigning the mixture. This study evaluated several CRM-modified mixture designs to address design and performance concerns; it also evaluated the volumetric and mechanistic properties of dense, SMA, and OGFC mixtures designed with unmodified asphalt cement, styrene-butadiene-styrene-modified asphalt cement and five crumb rubber sources. SuperPave volumetric parameters were evaluated to ascertain the impact of CRM on the design of these mixtures. Rutting and intermediate temperature cracking susceptibility were determined using the Hamburg Loaded Wheel Tracker (LWT) and semi-circular bend test (SCB), respectively. Solvent extraction and the ignition furnace were used to determine the asphalt content of the modified mixtures. The results showed that CRM improved the laboratory rutting resistance of the mixtures. However, the laboratory cracking resistance was decreased for the CRM-modified mixtures. Based on statistical analysis, additional asphalt content, reduced CRM dosage, and the use of polymer additives may mitigate the reduced laboratory cracking performance of the CRM-modified mixtures. The volumetric parameters were also affected by CRMs. The mixtures should be re-designed if the contractor anticipates using a CRM-modified asphalt cement.

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Physical properties of graphene-oxide modified asphalt and performance analysis of its mixtures using response surface methodology

International Journal of Pavement Engineering ◽

10.1080/10298436.2020.1804061 ◽

2020 ◽

pp. 1-15

Author(s):

Abbas Mukhtar Adnan ◽

Xue Luo ◽

Chaofeng Lü ◽

Jinchang Wang ◽

Zhiyi Huang

Keyword(s):

Response Surface Methodology ◽

Graphene Oxide ◽

Performance Analysis ◽

Physical Properties ◽

Response Surface ◽

Modified Asphalt ◽

And Performance

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Preparation and Performance Analysis of High-Viscosity and Elastic Recovery Modified Asphalt Binder

Advances in Civil Engineering ◽

10.1155/2019/6070685 ◽

2019 ◽

Vol 2019 ◽

pp. 1-16 ◽

Cited By ~ 1

Author(s):

Liangchen Qu ◽

Yingli Gao ◽

Hui Yao ◽

Dandan Cao ◽

Ganpeng Pei ◽

...

Keyword(s):

High Temperature ◽

Low Temperature ◽

Elastic Recovery ◽

Asphalt Binder ◽

Temperature Stability ◽

Crumb Rubber ◽

High Viscosity ◽

High Temperature Stability ◽

Modified Asphalt ◽

And Performance

This study presented the preparation and performance of a kind of high viscosity and elastic recovery asphalt (HVERA) by using some modifiers. The performance of styrene-butadiene-styrene (SBS), rock asphalt (RA), crumb rubber (CR), and stabilizing agent (SA) for different modifiers was investigated by conventional binder test. Effects of modifiers on the high- and low-temperature properties of HVERA were investigated. The dynamic viscosity (DV) test, dynamic shear rheometer (DSR), and bending beam rheometer (BBR) analysis indicated that the high- and low-temperature rheological properties of asphalt were improved attribute to the addition of mixture of modifiers. Meanwhile, the short-term aging and long-term aging were simulated by rolling thin film oven (RTFO) and pressure aging vessel (PAV) tests. Furthermore, the Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) measurements were conducted for obtaining the mechanism and microstructure distribution of the modified asphalt binders. From the test results in this study, it was evident that the addition of SBS, RA, CR, and SA into a neat asphalt binder could both significantly improve the viscosity of the binder at high temperature and lower the creep stiffness at low temperature, which was beneficial to better both high-temperature stability and low-temperature cracking resistance of asphalt pavements. It was proved that the high temperature grade of HVERA could be increased by increasing of RA and a proper percentage of modifiers could be improved by the low temperature grade of HVERA.

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