| In highway construction, alkaline or weak alkaline limestone, basalt aggregate are usually applied in asphalt pavement, but the application of limestone, basalt aggregate resources will be limited to the area and the amount. The Liu-Qian Expressway in the Dabie Mountain area where has a rich quality of the granite. Granite as acidic stone, stone hard, dense, strong wear resistance, can full play the role of embedded squeeze between aggregate, however the disadvantage of granite aggregate is the poor adhesion with the asphalt, and under the action of water is likely to cause the loss of asphalt film.Combined with the Liu-Qian Expressway Asphalt Pavement project, this paper researched the physical, mechanical properties of granite in the Dabie Mountains, and the design methods of granite asphalt mixture and the road performance, researched the evaluation and improvement measures of water stability of asphalt mixtures, laying the foundation of the local production of granite for wide application. First of all,we experiment from the macroscopic mechanical properties, lithologic analysis and micro-structure of granite, to determine the selection principles of granite aggregate and technical indicators. Then, using the Marshall immersion, freeze-thaw splitting, domestic rutting test and Hamburg rutting test study the impact of the various improvement measures on the granite asphalt mixture performance. The results show that: Mixed with liquid anti-stripping, lime, cement, can improve the water stability of asphalt mixture, but the effect of mixing lime is better than mixing liquid anti-stripping agent, and the optimum dosage of lime is 1.5%. Fine aggregate play a very important role in water stability for asphalt mixtures, using limestone instead of granite fine aggregate, can improve asphalt mixture performance against water damage. The test results of laboratory experiments and test section showed that the pavement performance of granite asphalt mixture is well.
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