Fiber-Reinforced Hot-Mix Asphalt: Idaho Case Study

Author(s):  
Ahmed Muftah ◽  
Amir Bahadori ◽  
Fouad Bayomy ◽  
Emad Kassem

This paper presents the findings of a research study to determine the benefits of fiber-reinforced asphalt mixtures used to mitigate distresses observed in the field. Control asphalt mixture test sections were constructed on US-30 in Idaho, along with fiber-reinforced asphalt mixture test sections. Three types of fibers were evaluated: Fiber 1 (i.e., aramid and polyolefin fiber), Fiber 2 (i.e., wax-treated aramid fiber), and Fiber 3 (i.e., glass fiber). Several laboratory tests were conducted on laboratory-prepared test samples and extracted field cores. The laboratory tests included dynamic modulus, flow number, Hamburg wheel-track test, indirect tensile test, creep compliance, and semicircular bending, in addition to performance evaluation with AASHTOWare Pavement ME Design software. The laboratory results showed no significant improvement to the properties of asphalt mixtures at the fiber content recommended by the manufacturer. However, the performance of asphalt mixtures did improve at a fiber dosage higher than the one recommended by the manufacturer. This study demonstrated the need to evaluate different fiber contents when asphalt mixtures are designed, because the dosage recommended by the manufacturer may not be optimal for various asphalt mixtures.

2014 ◽  
Vol 70 (4) ◽  
Author(s):  
Mohd Zul Hanif Mahmud ◽  
Haryati Yaacob ◽  
Ramadhansyah Putra Jaya ◽  
Norhidayah Abdul Hassan

This paper presents an investigation on the effects of flaky aggregates in asphalt mixture. In general, aggregate characteristics are critical to the performance of asphalt mixture. Therefore, flaky aggregate is normally avoided simply because it has significant contribution towards the gradation and reduces the interlocking characteristics of aggregates within asphalt mixture. In practice, it is recommended that the amount of flakiness aggregate should be limited to 25% or less. This study evaluates the mechanical properties of asphalt mixture specimens prepared with various percentages of flaky aggregates particularly 10%, 20% and 30% by the total weight of the mixture. Several laboratory tests were conducted including Marshall properties test, Indirect Tensile Modulus test and Dynamic Creep test. The results show that higher bitumen content is required with the increased in the amount of flaky aggregates added to mixture. Furthermore, greater amount of flaky aggregates tends to reduce the mixture’s resilient modulus and its resistance against permanent deformation.


Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7839
Author(s):  
Muhammad Aakif Ishaq ◽  
Filippo Giustozzi

Accurate characterisation and appropriate binder selection are essential to increase the load-induced cracking resistance of asphalt mixtures at an intermediate temperature. Hence, the primary goal of this study was to correlate the cracking resistance exerted by the binder with the cracking performance of asphalt mixtures. The laboratory-based experimental plan covered various types of laboratory tests specified by various agencies and road authorities to study the correlation of a neat bitumen and five polymer-modified binders with their corresponding asphalt mixtures. The fatigue life of the binders was assessed through a Linear Amplitude Sweep (LAS) test and statistically correlated with various load-induced cracking parameters from the indirect tensile test, semi-circular bending (SCB) test, and four points bending beam test (FPBB) of asphalt mixtures at 25 °C. Binders and mixes were further grouped depending on their polymeric family (i.e., modified with a particular type of polymer) to validate their statistical correlation. The indicator that mostly correlated the binder properties with the asphalt mixture properties is the secant modulus from the SCB test. Fatigue parameters obtained through LAS better explain the asphalt fatigue performance obtained through FPBB; specifically, asphalt tests at high strain levels (e.g., 400 micro strain) better correlate to the LAS fatigue parameter (Nf).


Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7060
Author(s):  
Mohammad Alharthai ◽  
Qing Lu ◽  
Ahmed Elnihum ◽  
Asad Elmagarhe

This study investigates the substitution of conventional aggregate with a Florida washed shell in open-graded asphalt mixtures and evaluates the optimal substitution percentage in aggregate gradations of various nominal maximum aggregate sizes (NMASs) (i.e., 4.75, 9.5, and 12.5 mm). Laboratory experiments were performed on open-graded asphalt mixture specimens with the coarse aggregate of sizes between 2.36 and 12.5 mm being replaced by the Florida washed shell at various percentages (0, 15, 30, 45, and 100%). Specimen properties relevant to the performance of open-graded asphalt mixtures in the field were tested, evaluated, and compared. Specifically, a Marshall stability test, Cantabro test, indirect tensile strength test, air void content test, and permeability test were conducted to evaluate the strength, resistance to raveling, cracking resistance, void content, and permeability of open-graded asphalt mixtures. The results show that there is no significant difference in the Marshall stability and indirect tensile strength when the coarse aggregates are replaced with Florida washed shell. This study also found that the optimum percentages of Florida washed shell in open-graded asphalt mixture were 15, 30, and 45% for 12.5, 9.5, and 4.75 mm NMAS gradations, respectively.


2015 ◽  
Vol 76 (14) ◽  
Author(s):  
Norhidayah Abdul Hassan ◽  
Nor Asniza Mohamed Abdullah ◽  
Nurul Athma Mohd Shukry ◽  
Mohd Zul Hanif Mahmud ◽  
Nur Zurairahetty Mohd Yunus ◽  
...  

Porous asphalt mixture is one of the alternative solutions to increase pervious surface area due to urbanization. The uniqueness of porous asphalt surface textures and internal structures allows the mixture to become a temporary storm-water retention and capable to channel excessive storm water. However, one of the major problems that affect the performance of porous asphalt mixtures is the clogging. Therefore, this study aims to determine the effect of clogging towards the permeability of porous asphalt. A total of 30 gyratory compacted samples were fabricated according to aggregate gradation recommended by Malaysia Public Works Department. The clogging materials were collected from two different location, residential area and major highway. The composition and characteristics of the clogging materials were investigated using Plastic Limit, Liquid Limit and Scanning Electron Microscope (SEM). The permeability test was conducted to investigate the permeability rate of the compacted samples based on different clogging material types, clogging concentrations and clogging cycles. In addition, the compacted samples were scanned using X-ray Computed Tomography to obtain the air voids distribution throughout the samples for comparison. It was found that higher concentration of clogging materials and clogging cycles reduced the rate of permeability. Clogging material collected from residential area has higher tendency to clog the void spaces compared to the one obtained from highway.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Yongjoo Kim ◽  
Jaejun Lee ◽  
Cheolmin Baek ◽  
Sunglin Yang ◽  
Sooahn Kwon ◽  
...  

A number of warm-mix asphalt (WMA) technologies are used to reduce the temperature at which the asphalt mixtures are produced and compacted, apparently without compromising the performance of the pavement. The main objective of this study is to determine whether the use of an innovative wax-based LEADCAP WMA additive influences the performance of the asphalt mixture, which is produced and compacted at significantly low temperatures. The WMA pavement using LEADCAP additive (WMA-LEADCAP) along with a control HMA pavement was evaluated with respect to their performances of rutting resistance, crack resistance, and viscoelastic property based on the laboratory dynamic modulus test, indirect tensile strength test, and in-door accelerated pavement test (APT) results. With the limited data carried out, the LEADCAP additive is effective in producing and paving asphalt mixture at approximately 30°C lower temperature than a control HMA mixture, and the performances of WMA-LEADCAP pavement are comparable to a control HMA pavement.


2011 ◽  
Vol 255-260 ◽  
pp. 3432-3436
Author(s):  
Xian Yuan Tang ◽  
Jie Xiao

This paper systematically elaborates the impact upon performance of emulsion asphalt cold reclaimed asphalt mixture by different RAP contents, through a series of testing on six cold reclaimed asphalt mixtures with various RAP contents, such as single axle compression test, 15°C indirect tensile strength (ITS) test, 40°C rutting test and -10°C low-temperature bending beam test. Testing results indicate that 15°C ITS decreases from around 0.75 MPa to 0.58 MPa with the RAP content of mixture increasing from 0% to 100%. 40°C dynamic stabilities reduce considerably from around 19,000 time/mm of 0% RAP mixture to 3,600 time/mm of 100% RAP mixture. -10°C failure strains only change from 1500με to 2000με.


2011 ◽  
Vol 243-249 ◽  
pp. 710-716 ◽  
Author(s):  
Ying Chun Cai ◽  
Yuan Xun Zheng

To study the influence of fiber on the water stability of asphalt mixtures, the optimum dosage of asphalt and fibers are studied by the method of Marshall test and rut test. The results demonstrate that the optimum dosage of asphalt and fibers are 4.63% and 0.30%, respectively. Then the improved effects of basalt fiber on water stability of asphalt mixtures are evaluated through immersed Marshall test and freeze-thaw splitting test according to related specifications. The results show that the freeze-thaw splitting strength and splitting strength without freeze-thaw of fiber-reinforced asphalt mixture are improved to some extent compared with control mixture. Splitting strength without freeze-thaw of basalt, polyester and xylogen fiber-reinforced asphalt mixture is increased by 36.4%, 15.4% and 6.2%, and freeze-thaw splitting strength is increased by 55.2%, 28.7% and 14.5%. It can be concluded that fiber can remarkably improved the water stability of asphalt mixtures, besides; the improvement effects of basalt fiber are superior to polyester fiber and xylogen fiber.


2021 ◽  
Vol 2102 (1) ◽  
pp. 012020
Author(s):  
J G Bastidas-Martínez ◽  
J C Ruge ◽  
R A G Zuluaga ◽  
L Medina

Abstract This paper evaluated the physical-mechanical characteristics of two asphalt mixtures. One mix with conventional asphalt and the other with asphalt modified with recycled rubber grain. For this purpose, the asphalt mix designs were made by means of the Marshall methodology. Subsequently, asphalt mixtures were manufactured to analyze the action of monotonic loads (indirect tensile strength) and dynamic loads (resilient modulus). Previously, each type of asphalt mix was subjected to short- and long-term aging conditions, following Aastho guidelines. It is concluded that the incorporation of recycled rubber grain makes the changes in mechanical properties with aging not very noticeable in relation to mixtures without this material.


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