Study On Optimization Design Of Asphalt Mixture Based On Superpave And Marshall Method

As the asphalt mixture design method, Marshall Method has been the specification of our country for many years, at the same time, Superpave system which from USA attracting many countries'attentions in recent years. We have got many achievements through a lot of researches and applications from the Superpave's coming to China. Superpave and Marshall Method has their own advantages and shortcomings through a comprehensive comparing between these two methods, so it has a positive significance for a long time to study the optimization design method based on Superpave and Marshall Method.The research of this paper shows that if you want to get a correct evaluation on the gradating type and interlocking condition of an aggregate gradation, you should comprehensively use the three parameters and chosen unit weight of Bailey Method, but that only use the three parameters or the chosen unit weight to evaluate is unreasonable. This paper also analyses the effects of each Bailey parameter during the process of the gradation design, and on this basis gives a trial-and-error thought to use Bailey Method to design the aggregate gradation of the asphalt mixture.The paper gives a much more reasonable optimization design method of the asphalt mixture through the contrast test of the calculation method about predicition asphalt content, the determination method of theoretical maximum density, the compaction methods of specimens, the determination method of optimum asphalt content and the test method of mixture performance of these two design methods. We also constructed entitative engineering, which called Wu Bu-Zi Zhou expressway with this method, and it showed a good application effect.The experiments show that Superpave gyratory compactor has much more compaction power than Marshall compactor, and its compaction mode can simulate the practical constructing much better. Through the optimum asphalt content designed by Superpave is lower than Marshall, but it has a better high and low temperature stability because of the mixture is much denser.The paper gives a method to calculate the compaction parameter, which is used to control the compactness in the construction to get a better service performance of the road surface.