Abstract
Flow-rutting is the main distress leading asphalt pavement to undergo premature maintenance, and is produced by the rapid accumulation of shear deformation in asphalt layers under high temperature and heavy loads. The excessive permanent deformation of the asphalt mixture at high temperature is related to the decrease of the material’s stability during the temperature increase and an unfavorable stress state, e.g., low confining pressure and high shear stress, which eventually leads to significant nonlinear viscoplastic behavior. In this research, dynamic modulus tests and repeated loading tests were carried out at 35 °C and 50 °C to analyze the deformation response of materials under a strain amplitude of <200 με and 400~500 μεs, respectively. Based on the in-lab repeated loading tests, the total deformation of the asphalt mixture in each loading and rest cycle was divided into three parts, being elastic, viscoelastic, and viscoplastic strain, and the measurement of the axial and lateral strain of cylindrical samples was realized with the aid of optical fiber Bragg grating strain sensors. It was found that the experimental index of the ratio between lateral strain and longitudinal strain (RLSLS), derived, but distinguished, from Poisson’s ratio defined limited in elastic strain, can characterize the deformation in viscoelastic and viscoplastic behaviors of the mixes. Furthermore, the indices of dynamic modulus, phase angle, complex Poisson’s ratio, stiffness, and creep rate of four types of mixes containing different volcanic ash fillers and asphalt binders at 35 °C and 50 °C were systematically analyzed by the jointed experiments of modified dynamic modulus tests and repeated loading tests, and their consistent trending to the RLSLS index was obtained.
Highlights
Flow-rutting (FR) is one of the most harmful forms of distress on high-grade asphalt pavement
The material properties at higher temperatures can be characterized at low testing freapparatus in the standard dynamic modulus (DM) test was replaced by an optical fiber Bragg grating (OFBG) strain sensor in the modified quencies according to the time-temperature superposition principle (TTSP) [30]
The axial and lateral deformation features of four hot mixed asphalt (HMA), using two volcanic ash (VA)-SBS mixtures and VA-base mixtures at 50 ◦ C were more significant than the difference in VA fillers combined with the binder of base asphalt and SBS-modified asphalt, were sysve, indicating that (i) VA-SBS mixtures had better resistance to permanent deformation and tematically analyzed at 35 °C and 50 °C through the DM test and repeated load permanent deformation (RLPD) test
Summary
Flow-rutting (FR) is one of the most harmful forms of distress on high-grade asphalt pavement. Based on the relationship between the material and structure of asphalt pavement, the permanent shear deformation in asphalt layers is usually introduced by the coupling effects of the following factors: (1) high-temperature conditions that induce more significant viscoplastic behavior of the asphalt mixture and results in higher permanent deformation;. Precise evaluation methods and indicative indices are still needed to reflect the development of permanent deformation within asphalt pavement under high temperature and complex loading conditions to further improve and predict the performance and stability of an asphalt mixture. The common deformation sensor, linear variable differential transformer (LVDT) that adhered to HMA samples, is prone to soften under high temperatures, which affects the testing accuracy To overcome this problem, an optical fiber Bragg grating (OFBG) strain sensor was adopted to measure the Materials 2022, 15, 1882 lateral and longitudinal strain of cylindrical HMA specimens in this study. By calculating the RLSLS corresponding to these strains, the effects of different types of VA and asphalt binders on deformation behavior were analyzed and the correlation between RLSLS and the shear permanent deformation of the HMA was discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
