TECHNICAL NOTE. A COMPARISON OF THE MARSHALL AND THE INDIRECT TENSILE TESTS IN RELATIO N TO ASPHALT MIXTURE DESIGN.

Oxidative aging takes place in bituminous materials during the construction and service life of asphalt pavements and has a significant effect on their performance. In this study, porous asphalt cores were obtained from field test sections each year from 2014 to 2017. The evolution of the properties of the field cores and the recovered bitumen with time was investigated. Cyclic indirect tensile tests were performed to determine changes in the mechanical behavior of porous asphalt due to aging. Additionally, bitumen was extracted and recovered from 13 mm slices along the depth of the cores. The rheological and chemical properties of the recovered bitumen, as well as that of original bitumen aged in standard short- and long-term aging protocols, were investigated by means of dynamic shear rheometer and Fourier transform infrared spectrometer. The results show that the degree of aging is spatially dependent, resulting in a stiffness gradient within the asphalt layer. Moreover, the results demonstrate a weak relation between field aging and the standard laboratory aging protocols.

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Preliminary Studies to Use Textile Fibers Obtained from Recycled Tires to Reinforce Asphalt Mixtures

Romanian Journal of Transport Infrastructure ◽

10.2478/rjti-2018-0009 ◽

2018 ◽

Vol 7 (2) ◽

pp. 14-30

Author(s):

Jorge C. Pais ◽

António Ferreira ◽

Caio Santos ◽

Paulo Pereira ◽

Davide Lo Presti

Keyword(s):

Asphalt Mixture ◽

Tensile Tests ◽

Crumb Rubber ◽

Asphalt Mixtures ◽

Asphalt Pavements ◽

Valuable Resource ◽

Scrap Tires ◽

Textile Fibers ◽

Asphalt Rubber ◽

Indirect Tensile

Abstract The use of crumb rubber in the modification of asphalt has occurred because of the problems related to disposal of scrap tires. However, the use of scrap tires in asphalt pavements, known as asphalt rubber pavements, can minimize environmental impacts and maximize conservation of natural resources. The textile fibers from recycled tires are typically disposed of in landfills or used in energetic valorization, but similar to other fibers, they can be used as a valuable resource in the reinforcement of engineering materials such as asphalt mixtures. Thus, this work aims at studying the use of textile fibers recycled from ground tires in the reinforcement of conventional asphalt mixtures. The application of textile fibers from ground tires was evaluated through laboratory tests on specimens extracted from slabs produced in the laboratory. Indirect tensile tests were performed on a series of nine asphalt mixtures with different fiber and asphalt contents and compared with a conventional mixture. The results obtained from a 50/70 pen asphalt were used to define three asphalt mixture configurations to be used with 35/50 pen asphalt. The results indicate that the textile fibers recycled from used tires can be a valuable resource in the reinforcement of asphalt mixtures.

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Investigating the Effects of Chopped Basalt Fiber on the Performance of Porous Asphalt Mixture

Advances in Materials Science and Engineering ◽

10.1155/2019/2323761 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

Sheng Wang ◽

Aihong Kang ◽

Peng Xiao ◽

Bo Li ◽

Weili Fu

Keyword(s):

Tensile Strength ◽

Fiber Length ◽

Asphalt Mixture ◽

Basalt Fiber ◽

Tensile Tests ◽

Asphalt Mixtures ◽

Basalt Fibers ◽

Strength Performance ◽

Porous Asphalt ◽

Indirect Tensile

Porous asphalt mixture is a type of asphalt mixture with good drainage. However, it has poor tensile strength performance and durability. Chopped basalt fibers (CBF) have been proved to be an effective additive to improve the mechanical and fatigue performance of asphalt mixtures, but little attention has been paid on porous asphalt mixture. This paper examined the effect of chopped basalt fibers with different lengths (nonfiber, 3 mm, 6 mm, 9 mm, and 12 mm) and contents (3% and 4%) on the performance of the porous asphalt mixture. A series of tests were conducted to figure out the optimum fiber length and content, including draindown test, cantabro abrasion test, freeze-thaw split tensile test, wheel tracking test, low-temperature cracking resistance test, and four-point bending beam test. Thereafter, indirect tensile tests at different temperatures were conducted to investigate the tensile strength properties of porous asphalt mixtures with optimum fiber length and content. Besides, the macroscopic and microscopic morphology of fracture sections of the samples after indirect tensile tests were studied by using a single-lens reflex (SLR) camera and scanning electron microscopy (SEM) so as to further explore the reinforced mechanism of chopped basalt fibers. The results show that the addition of chopped basalt fibers can generally improve the performance of porous asphalt mixture since chopped basalt fibers form a three-dimensional network structure in the porous asphalt mixture.

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Indirect Tensile Test (IDT) to Determine Asphalt Mixture Performance Indicators during Quality Control Testing in New Jersey

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198118793276 ◽

2018 ◽

Vol 2672 (28) ◽

pp. 394-403 ◽

Cited By ~ 7

Author(s):

Thomas Bennert ◽

Edwin Haas ◽

Edward Wass

Keyword(s):

Quality Control ◽

Tensile Test ◽

Asphalt Mixture ◽

Performance Testing ◽

Fatigue Cracking ◽

Test Methods ◽

Mixture Design ◽

Indirect Tensile Test ◽

Quality Control Testing ◽

Indirect Tensile

In recent years, there has been a growing interest in incorporating performance testing during the mixture design and quality control testing of asphalt mixtures. The move toward utilizing performance related specifications (PRS) and balanced mixture design concepts have pushed the need for asphalt mixture performance testing to the forefront. Numerous researchers have proposed a variety of laboratory tests that have showed promise at predicting asphalt mixture performance, yet most of these test methods are never adopted due to a number of issues often cited by the asphalt industry: (1) equipment cost; (2) equipment/test method complexity; and (3) time/labor effort required. The research presented here summarizes the effort to evaluate the indirect tensile test (IDT) as a potential performance indicator for hot-mix asphalt that can be easily utilized during quality control testing at an asphalt plant. Utilizing the same test equipment and basic procedure, both high-temperature rutting and intermediate-temperature fatigue cracking can be evaluated in a timely manner. Comparison testing to more standardized and accepted rutting and fatigue cracking test methods have shown excellent agreement, indicating that the suite of IDT tests have potential for adoption within a quality control testing program. Examples of criteria are given utilizing the New Jersey Department of Transportation’s (NJDOT) PRS.

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Benefits and Applications of Utilizing Agency Asphalt Mixture Design Historical Records

Green Streets, Highways, and Development 2013 ◽

10.1061/9780784413197.004 ◽

2013 ◽

Author(s):

Jesse D. Doyle ◽

William J. Robinson ◽

Isaac L. Howard

Keyword(s):

Asphalt Mixture ◽

Mixture Design ◽

Historical Records

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Rejuvenation Mechanism of Asphalt Mixtures Modified with Crumb Rubber

CivilEng ◽

10.3390/civileng2020020 ◽

2021 ◽

Vol 2 (2) ◽

pp. 370-384

Author(s):

Hossein Noorvand ◽

Kamil Kaloush ◽

Jose Medina ◽

Shane Underwood

Keyword(s):

Tensile Strength ◽

Dynamic Loading ◽

Creep Compliance ◽

Asphalt Mixture ◽

Crumb Rubber ◽

Indirect Tensile Strength ◽

Laboratory Evaluation ◽

Strength Testing ◽

Noise Mitigation ◽

Indirect Tensile

Asphalt aging is one of the main factors causing asphalt pavements deterioration. Previous studies reported on some aging benefits of asphalt rubber mixtures through laboratory evaluation. A field observation of various pavement sections of crumb rubber modified asphalt friction courses (ARFC) in the Phoenix, Arizona area indicated an interesting pattern of transverse/reflective cracking. These ARFC courses were placed several years ago on existing jointed plain concrete pavements for highway noise mitigation. Over the years, the shoulders had very noticeable and extensive cracking over the joints; however, the driving lanes of the pavement showed less cracking formation in severity and extent. The issue with this phenomenon is that widely adopted theories that stem from continuum mechanics of materials and layered mechanics of pavement systems cannot directly explain this phenomenon. One hypothesis could be that traffic loads continually manipulate the pavement over time, which causes some maltenes (oils and resins) compounds absorbed in the crumb rubber particles to migrate out leading to rejuvenation of the mastic in the asphalt mixture. To investigate the validity of such a hypothesis, an experimental laboratory testing was undertaken to condition samples with and without dynamic loads at high temperatures. This was followed by creep compliance and indirect tensile strength testing. The results showed the higher creep for samples aged with dynamic loading compared to those aged without loading. Higher creep compliance was attributed to higher flexibility of samples due to the rejuvenation of the maltenes. This was also supported by the higher fracture energy results obtained for samples conditioned with dynamic loading from indirect tensile strength testing.

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Evaluation of Asphalt Mixture Performance Using Cracking and Durability Tests at a Full-Scale Pavement Facility

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/03611981211021856 ◽

2021 ◽

pp. 036119812110218

Author(s):

Amir Golalipour ◽

Varun Veginati ◽

David J. Mensching

Keyword(s):

Performance Test ◽

Asphalt Mixture ◽

Performance Testing ◽

Field Performance ◽

Optimization Procedure ◽

Cyclic Fatigue ◽

Intermediate Temperature ◽

Index Test ◽

Reclaimed Asphalt ◽

Indirect Tensile

In the asphalt materials community, the most critical research need is centered around a paradigm shift in mixture design from the volumetric process of the previous 20-plus years to an optimization procedure based on laboratory-measured mechanical properties that should lead to an increase in long-term pavement performance. This study is focused on advancing the state of understanding with respect to the value of intermediate temperature cracking tests, which may be included in a balanced mix design. The materials included are plant-mixed, laboratory-compacted specimens reheated from the 2013 Federal Highway Administration’s (FHWA’s) Accelerated Loading Facility (ALF) study on reclaimed asphalt pavement/reclaimed asphalt shingle (RAP/RAS) materials. Six commonly discussed intermediate temperature (cracking and durability) performance testing (i.e., Asphalt Mixture Performance Tester [AMPT] Cyclic Fatigue, Cantabro, Illinois Flexibility Index Test [I-FIT], Indirect Tensile Cracking [ITC, also known as IDEAL-CT], Indirect Tensile Nflex, and Texas Overlay Test) were selected for use in this study based on input from stakeholders. Test results were analyzed to compare differences between the cracking tests. In addition, statistical analyses were conducted to assess the separation among materials (lanes) for each performance test. Cyclic fatigue and IDEAL-CT tests showed the most promising results. The ranking from these two tests’ index parameters matched closely with ALF field performance. Furthermore, both showed reasonable variability of test data and they were successful in differentiating between different materials.

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MECHANICAL PERFORMANCE OF ASPHALT MIXTURE CONTAINING CUP LUMP RUBBER

Jurnal Teknologi ◽

10.11113/jt.v81.13857 ◽

2019 ◽

Vol 81 (6) ◽

Author(s):

Norfazira Mohd Azahar ◽

Norhidayah Abdul Hassan ◽

Ramadhansyah Putra Jaya ◽

Hasanan Md. Nor ◽

Mohd Khairul Idham Mohd Satar ◽

...

Keyword(s):

Mechanical Performance ◽

Resilient Modulus ◽

Permanent Deformation ◽

Asphalt Binder ◽

Asphalt Mixture ◽

Modified Asphalt ◽

Dynamic Creep ◽

Aging Conditions ◽

Public Work Department ◽

Indirect Tensile

The use of cup lump rubber as an additive in asphalt binder has recently become the main interest of the paving industry. The innovation helps to increase the natural rubber consumption and stabilize the rubber price. This study evaluates the mechanical performance of cup lump rubber modified asphalt (CMA) mixture in terms of resilient modulus, dynamic creep and indirect tensile strength under aging conditions. The CMA mixture was prepared using dense-graded Marshall-designed mix and the observed behavior was compared with that of conventional mixture. From the results, both mixtures passed the volumetric properties as accordance to Malaysian Public Work Department (PWD) specification. The addition of cup lump rubber provides better resistance against permanent deformation through the enhanced properties of resilient modulus and dynamic creep. Furthermore, the resilient modulus of CMA mixture performed better under aging conditions.

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