Study On Application Of Regeneration Asphalt Mixture In Flexible Base

To conserve resources and protect environment through recycling a large quantities of milling materials from asphalt pavement renovation effectively, this paper study on paving flexible base with the milling materials. Through laboratory experiments, theoretical analysis, calculation and other means mainly, the paper systematically and deep researches the main technological property of old asphalt and mineral aggregate in RAP, design method and pavement performance of regeneration flexible base asphalt mixture composition and structure of regeneration flexible base and so on. Now we can conclude:When asphalt pavement has been effected by environment and loads about7-8years, to old asphalt, penetration degree and ductility decrease by over70%, softening point increases by about50%, and density increases a bit; besides, to old mineral aggregate, gradation turns fine, but the mechanical index of coarse aggregate, such as crushing value and Los Angeles abrasion ratio, can meet the specification requirements of freeway asphalt pavement.Through the mix proportion design and pavement performance experiments of regeneration asphalt mixture, which includes four RAP blending ratios (0%、15%、30%and45%) and three kinds of gradation, the paper forms the composition design method of regeneration asphalt mixture based on Marshall test and the law that mechanical strength, water stability, high temperature performance and low temperature performance of regeneration asphalt mixture are influenced by RAP blending ratio. And optimum oil-stone ratio of regeneration asphalt mixture can be confirmed by calculating oil film thickness, drain-down test, Cantabro raveling test. With RAP blending ratio increasing, high temperature performance and mechanical strength improve observably, but water stability and low temperature performance decrease.Use mechanics software to calculate the design index and the fatigue life of the pavement structure with regeneration flexible base, including that analyze the influence, which is produced by different RAP content and thickness of regenerated base, on the design deflection value, bottom layer tensile stress, shear stress and fatigue life.