Study on the Fatigue Property for Aged Asphalt Mixtures by Using Four Point Bending Tests

The effects of aging on the fatigue property of polymer modified asphalt mixtures are investigated in this paper. Two kinds of aging procedures are adopted for the aging of specimens prepared with polymer modified asphalt mixtures. One is the short-time aging which means that the hot asphalt mixtures was heated in the oven for 4 hours at 135°C before compacted; The other called natural aging, with the original specimen exposed in the sunlight and subjected to the rain and temperature change for 3, 6 and 9 months. Four-Point Bending Test was conducted to evaluate fatigue properties of aged asphalt mixtures at 15°C compared with the original specimens. Test results indicate that the fatigue line of aged specimens have the same tendency as the original asphalt mixtures. However, the life of aged specimen is decreased significantly when compared with the original ones, especially of the natural aged specimens.

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Four-point bending mechanical behavior of aged asphalt mixtures containing charcoal

International Journal for Innovation Education and Research ◽

10.31686/ijier.vol7.iss10.1794 ◽

2019 ◽

Vol 7 (10) ◽

pp. 460-472

Author(s):

Alemar Pereira Torres ◽

Igor Nonato Almeida Pereira ◽

Juliano Rodrigues Spínola ◽

Alex Gomes Pereira ◽

Consuelo Alves da Frota

Keyword(s):

Mechanical Behavior ◽

Aging Process ◽

Mechanical Characteristics ◽

Asphalt Mixtures ◽

Bending Test ◽

New Materials ◽

Molding Process ◽

Four Point Bending ◽

Aged Asphalt ◽

Four Point Bending Test

The asphalt coating is the layer responsible for resisting the traffic stresses of a highway. However, the search for new materials to mitigate environmental impacts and improve pavement quality is increasing. Thus, the mechanical behavior of asphalt mixtures was analyzed through the four-point bending test after the molding process and aged, with the participation of residues in the form of charcoal. The frequencies of 1Hz, 3Hz, 5Hz, 10Hz, 20Hz and 1Hz are considered at temperatures of 25°C and 40°C. The aging process contributed to improve the mechanical characteristics of the charcoal mixture at a temperature of 25 ° C, considering that there was an increase in stiffness at frequencies from 1 to 20 Hz, as well as a reduction in phase angle at frequencies of 3 Hz. , 5 Hz, 10 Hz and 20 Hz.

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Effect of Different Polymer Modifiers on the Long-Term Rutting and Cracking Resistance of Asphalt Mixtures

Materials ◽

10.3390/ma14123359 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3359

Author(s):

Bangwei Wu ◽

Chufan Luo ◽

Zhaohui Pei ◽

Ji Xia ◽

Chuangchuang Chen ◽

...

Keyword(s):

Asphalt Mixtures ◽

Bending Test ◽

Cracking Resistance ◽

Rutting Resistance ◽

Modified Asphalt ◽

Significant Difference ◽

Polymer Modified Asphalt ◽

Aging Stage ◽

Polymer Modifiers

To evaluate the long-term performances of different polymer-modified asphalt mixtures, three modifiers were chosen to modify AC-13 (defined as the asphalt concrete with the aggregate nominal maximum particle size of 13.2 mm); namely, high viscosity modifier (HVM), high modulus modifier (HMM), and anti-rutting agent (ARA). The deformation and cracking resistance of different polymer-modified mixtures were checked at different aging conditions (unaged, short-term aged, and long-term aged for 5, 10, and 15 days respectively). The results of the Hamburg wheel-track test and uniaxial penetration test (UPT) showed that the rutting resistance of all asphalt mixtures changed in a V-shape as the aging progressed. From the unaged stage to the long-term aging stage (5 days), the rutting resistance decreases gradually. While after the long-term aging stage (5 days), the rutting resistance increases gradually. Results from the semicircular bending test (SCB) and the indirect tensile asphalt cracking test (IDEAL-CT) indicated that the cracking resistance of all the mixtures gradually decline with the deepening of the aging degree, indicating that aging weakens the crack resistance of asphalt mixtures. Additionally, test results showed that the rutting resistance of ARA AC-13 (defined as AC-13 containing ARA) is the best, the cracking resistances of ARA AC-13, HMM AC-13 (defined as AC-13 containing HMM) and HVM AC-13 (defined as AC-13 containing HVM) have no significant difference, and different polymer modifiers had different sensitivities to aging due to the polymer content and the type of modifier. The conclusions of this study help to further understand the long-term performance of polymer-modified asphalt mixtures during service life and to help guide the selection of modifiers for mixtures.

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Performance Evaluation of Polymer Modified Asphalt Mixtures

International Journal of ICT-aided Architecture and Civil Engineering ◽

10.21742/ijiace.2014.1.2.03 ◽

2014 ◽

Vol 1 (2) ◽

pp. 33-50

Author(s):

Eslam Magdy Mohammed Deef-Allah ◽

◽

Ahmed Mohamady ◽

Keyword(s):

Performance Evaluation ◽

Asphalt Mixtures ◽

Modified Asphalt ◽

Polymer Modified Asphalt

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Mechanical Characteristics of Graphene Nanoplatelets-Modified Asphalt Mixes: A Comparison with Polymer- and Not-Modified Asphalt Mixes

Materials ◽

10.3390/ma14092434 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2434

Author(s):

Laura Moretti ◽

Nico Fabrizi ◽

Nicola Fiore ◽

Antonio D’Andrea

Keyword(s):

Fatigue Resistance ◽

Graphene Nanoplatelets ◽

Asphalt Mixtures ◽

Asphalt Binders ◽

Asphalt Mixes ◽

Modified Asphalt ◽

Bituminous Mixtures ◽

Water Sensitivity ◽

Polymer Modified Asphalt ◽

Mechanical Performances

In recent years, nanotechnology has sparked an interest in nanomodification of bituminous materials to increase the viscosity of asphalt binders and improves the rutting and fatigue resistance of asphalt mixtures. This paper presents the experimental results of laboratory tests on bituminous mixtures laid on a 1052 m-long test section built in Rome, Italy. Four asphalt mixtures for wearing and binder layer were considered: two polymer modified asphalt concretes (the former modified with the additive Superplast and the latter modified with styrene–butadiene–styrene), a “hard” graphene nanoplatelets (GNPs) modified asphalt concrete and a not-modified mixture. The indirect tensile strength, water sensitivity, stiffness modulus, and fatigue resistance of the mixtures were tested and compared. A statistical analysis based on the results has shown that the mixtures with GNPs have higher mechanical performances than the others: GNP could significantly improve the tested mechanical performances; further studies will be carried out to investigate its effect on rutting and skid resistance.

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