Study On High Temperature Performance Of Mastic Asphalt Mixture

Asphaltic cement, filler and fine aggregate constitute Mastic epure in which we putcoarse aggregate to form a non-porous impermeable mixture. This is called Mastic Asphaltmixture. Mastic Asphalt mixture is widely used in Europe. Especially in England, it has beenadopted in the suspension bridge deck pavement for over30years. Asphaltic cement is mixedby a kind of ordinary asphalt (penetration of60to70) and Trinidad Lake Asphalt (TLA)according to a certain percentage. The latest standard requires that TLA accounts for70%.Mastic Asphalt can be mixed at the worksite (mixing temperature of200℃to230℃) orprefabricated in a factory and cooling into a25kg block in order to be transported to theconstruction site to be re-heated to melt. When we start construction, first, the coarseaggregate (single particle size：10~14mm) whose proportion accounted for45%of the totalarea is added, then it is heated and stirred to form Mastic Asphalt mixture. Second, use thespecial paver to do pouring type paves. At last, press the ready-mixed asphalt gravel into thesurface (nominal dimensions of14mm). Mastic Asphalt mixture has excellent waterresistance and durability, with a life expectancy of25years. Since the1960s, Mastic Asphaltmixture is widely used as a wear layer or waterproof layer, and it has been applied in China’sHong Kong Tsingma Bridge and Jiangyin Yangtze River Highway Bridge Deck Pavement.On the basis of the existing research, aiming at the characteristics of domestic asphaltmixture high temperature performance evaluation methods and indicators, this paper does theresearch on high temperature performance of Mastic Asphalt mixture. Adopting technologyresearch and laboratory experiment, this paper analysis the technical requirements and methodof mix design of Mastic Asphalt mixture. Meanwhile, it analyzes load and aging’s influenceon the high temperature properties of Mastic Asphalt mixture by laboratory experiments.First of all, according to BS1447-1988the technical requirements, this paper does theresearch on the basic performance of stones used in Mastic Asphalt mixture, and the researchon the basic performance and dynamic shear of Asphaltic cement as well. Besides, it alsoanalyzes the influence of TLA dosage, temperature and aging on Asphaltic cement.Second, through the analysis to mix design principle of Mastic Asphalt mixture, theexperiment uses the gradation and the best soluble asphalt content mixing molding specimenswithin BS1447:1988standard in order to do performance evaluation and test on MasticAsphalt mixture.Third, through the study on the evaluation method of high-temperature performance of Mastic Asphalt mixture, this research chooses the suitable high temperature performanceevaluation methods and indicators of Mastic Asphalt mixture and analyzes the connectiondegree of high temperature performance influential factors within gray relational analysismethod.Finally, based on several common paving forms of Mastic Asphalt mixture about steelbridge deck pavement and according to characteristics of Steel Deck Pavement load and aging,this paper analyzes the influence of load (standard load, upload10%upload20%) and aging(original sample, short-term aging and long-term aging) on high-temperature performance ofMastic Asphalt mixture.