Research On The Rutting Performance Of Asphalt Mixtures In Chongqing

With the rapid development of highway construction in China since the 1990s, early diseases happen in the asphalt pavement in large-scale construction process, especially high temperature rutting, and Chongqing is particularly prominent. The high temperature lasts longer from June to September every year, and it rains a lot from May to October in Chongqing area, coupled with heavy traffic, the role of asphalt mixture in Chongqing propose more stringent performance requirements. Adapted to the characteristics of regional climate in Chongqing, the mixture design gradation range for engineering using are problems to be solved.In this paper, research reports on asphalt pavement during the similar climatic zones at home and abroad are collected, and field studies of high-temperature rutting in the Chongqing area are done, and the engineering experience is summarized. Raw materials commonly used in Chongqing area are selected, and three types of dense gradation mixes AC-20, AC-16 and AC-13 are tested.Bulk density tests are used to determine the optimum proportions of coarse aggregate in the mixes, and the smaller voids in a mix are thought to be the better one. Five kinds of the shape of fine aggregate gradation calculated by 5 different N values are selected through Wheel Tracking Test and Freeze-Thaw Split Test to find the best of fine aggregate composition. Five kinds of percent passing of key sieve, which is five weight ratio of the composition of mixture gradation, are used to determine the most proper ratio through Wheel Tracking Test and Freeze-Thaw Split Test. On this basis, all aspects of road performance requirements are integrated, and the mixture design gradation ranges of AC-20, AC-16, AC-13 adapted to the characteristics of Chongqing regional climate are resulted to improve the rutting resistance capability in Chongqing.