Abstract
Asphalt mixture is a multiphase particulate material composed of aggregate, asphalt and filler. The deformation property of asphalt mixture is an external reflection of aggregate slip behaviour. To evaluate the high-temperature deformation properties of asphalt mixture, an aggregate slip device was developed and aggregate slip tests were conducted on five asphalt mixtures for different gradations under different test conditions. Four evaluation parameters, the slip failure load (Fs), the slip failure deformation (Ds), slip modulus parameter (M) and slip energy index (SEI), were obtained according to the load–displacement curves. The relationship between these parameters and rut depth (RD) was analysed. The effects of test temperature and asphalt content on slip resistance of asphalt mixture are studied in this research. The results indicate that the parameter Fs has limitations for large nominal maximum particle-size mixture, and SEI is an effective parameter to evaluate the aggregate slip properties for different nominal maximum particle-size asphalt mixtures. SEI has the strongest relationship to RD, which is the best parameter to evaluate the slip deformation behaviour of asphalt mixture. With the increase in asphalt content, SEI has a peak value and a valley value. When the optimum asphalt content is used in asphalt mixture, aggregate skeleton effect and asphalt cohesive force can both reach a high level, and asphalt mixture has the best deformation resistance.
Acknowledgements
This research was supported by Applied Basic Research Project by the Ministry of Transport of China (No. 2014319812151), Natural Science Basic Research Plan in Shaanxi Province of China (No. 2014JQ7242) and the National Natural Science Foundation of China (No. 51008031).
Notes
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