Research On Rheological Characteristics Of Asphalt Mortar And Gradation Optimization Based On Superpave

Superpave is the end products in area of asphalt and mix after the Strategic Highway Research Program (SHRP) have been finished. Since Superpave is introduced into china, the reaction of all circles is greater. The research organization and universities of highway and petroleum profession purchase part or complete Superpave equipment. There are many Superpave test road and projects in provinces cities. Superpave has become another hot issue after SMA technology.Even if Superpave is good, for some asphalt especially the modified asphalt, its performance specification cannot guarantee that the asphalts with same PG have the identical or similar field performance. Though bailey method can give engineers some advices in gradation optimization, we cannot simply use foreign law because there is much discrepancy such as compaction method, the parameter value scope, and more important we don't know the relationship between the parameters and the field performance. It's the better way to carry out the research combined the reality of our nation.To solve above-mentioned problem, this paper mainly research on the two parts, firstly , the asphalt mortar is studied by using the Superpave equipments such as DSR, BBR and DTT .the relationship between the asphalt mortar and the equipments' working parameters, Theological characteristics in the high, mediate and low temperature have been gained. The mechanism in asphalt mortar is discussed; it's found that the Buttlar and Hashin formula can predict the volume-filling reinforcement. In order to predict the reinforcement mechanisms, the equivalent volume-filling reinforcement is put forward, the correlation between the calculated value and the actual measurement is good. Secondly, the calculate formula of Interfere theory have been proved with graphic method. The relation between value and theoretical spheroid accumulation model has been gained with the help of interfere theory and fracture theory. The theoretical scope of n and the theatrical value of maximum density line have been gotten. Through the comparison with the specification of ASTM and our nation, it's proved that the theoretical value of n is reasonable. The paper still discusses the influence of Superpave on our gradation. The paper System introduces the bailey method including the basic concept, evaluation method and parameter scope. Through testing design, the relation between the bailey method's parameter and the volume parameter, the performance parameters have concluded. Using the marshal compaction method. On the basis of research results in others, the paper put forward the bailey method parameter's scope of 12.5 mm NMAS mixture and the selection principle.This paper discusses the issue as followed aspects: the Theological characteristics of asphalt mortar, the asphalt mortar mechanism, gradation theory and the gradation optimization by bailey method. In conclusion, which works for the in-depth application of Superpave. This paper will be useful to build the mixture design method based on field performance.