Asphalt Mixture Ratio Design Method In Chill Region

Based on the reconstruction of National Road 213 Langmusi to Chuanzhusi, which is characterized of high latitude and frigidity, property tests of asphalt mixtures are carried out. Analysis and researches are accordingly followed, including: temperature of rolling, dosage of asphalt and method of molding specimen, in which water stability and the anti-crack ability in cold temperature are focused.It is concluded that all properties of asphalt concrete (AC) are closely correlated with temperature of rolling. To guarantee the construction of AC, therefore, the temperature of rolling must be strictly executed and supervised. Analyses also testify that the dosage of asphalt influences the performance of AC. The optimum for type AC-13 here is 5.0%.Considering the optimum for molding, in the process of Marshall specimen manufacture, 2×85, rather than 2×75, is recommended to achieve a 4% voids percentage. Furthermore, it is suggested that every criteria should be increased, if the Gyratory Rolling is utilized.For additives, it is approved that additives can strengthen the cohesion between acid aggregate, granite especially, and asphalt, which then enhance the performance of AC. However, different additives lead to different performance.Finally, some suggestion for AC design procedure in high latitude and frigidity are proposed, including: the key guideline should be anti-crack ability in cold temperature, anti-freezing ability and anti-aging ability; the dense gradation is better than other kinds; a critical temperature of rolling need to be figured out based on laboratory tests; the VV=4% can be set as goal when choosing the optimum dosage of asphalt; additives can improve the property of acid aggregate for AC.