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Through the long-term aging state of 9()二 matrix asphalt, SBS modified asphalt, extreme cold asphalt, rubber asphalt, low temperature bending beam flow under different low temperature (-12, -18-24 and --30 °C) conditions (BBR) test-analyzes the creep stiffness modulus and creep rate of 4 kinds of asphalts at 6() s with temperature; based on the fractional differential theory, it proves the fractional calculus of viscoelastic behavior of viscoelastic materials, and the fractional derivative viscoelastic model is used to fit the asphalt BBR creep stiffness curve, and the relevant model parameters and physical meaning are determined. At the same time-a physical equation between the 1 ow-temperature creep stiffness modulus S and creep ratemof the asphalt is constructed based on the fractional derivative viscoelastic model. The results show that the BBR tests the relationship between the creep stiffness modulus S and the creep rate m of the four asphalts at 6() s. As the asphalt undergoes glass transition, when the temperature is lower than 一1 8 °C, the four asphalts the creep stiffness modulus S and creep rate m often change abruptly and do not show a significant linear change;the fractional derivative viscoelastic model can more accurately describe the low-temperature performance of asphalt in BBR tests. Model parameters A and a fractional derivative order has physical meaning. A is the low-temperature deformation factor of asphalt. The larger the parameter A, the better the low-temperature crack resistance of the four asphalts. The larger the value of the parameter fractional derivative ord era, the stronger the low-temperature relaxation ability of the 4 types of asphalt, the fractional derivative ord er. The second a is the low-temperature relaxation factor of the asphalt, and the fractional derivative order can well estimate the low-temperature creep rate of the asphalt; based on the fractional derivative viscoelastic model, the asphalt low-temperature creep stiffness modulus S and creep rate m the physical equations between them can be characterized by creep compliance rate J7(t), and by increasing the fractional derivative order a of the model parameter, a larger creep compliance rate 丿'(方)can be obtained to improve the low temperature crack resistance of the asphalt. The variable compliance rate 厂(方)is a good indicator of the low-temperature performance of asphalt. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)