Study On The Application Of Expressway Asphalt Pavement Flexible Base (Asphalt Treated Crushed Stone)

Because of its superior bearing capacity, integral and durability, semi-rigid base has been the main pavement structure in our country for many years. But, with the practical application and research on this kind of pavement structure used in high-type highway, many diseases including reflection cracks, one of the most serious distresses occurred.In order to resolve these problems mentioned above, asphalt treated crushed stone flexible bas(eATB) has been put forward in pavement structure design. It, different from semi-rigid base that is often used in our country, belongs to the category of flexible base. It has great strength, rigidity and good capability of fatigue resistance, and can control and reduce reflecting crack. Asphalt treated crushed stone mixture has fine pavement performances. ATB is widely used abroad, but seldom used at home. The study on ATB has just started in our country.Based on consulting a large number of domestic and foreign documents concerning this subject, the paper proposes pavement performances requirement of ATB. Using GTM method to do gradation of ATB mixture and determine the optimum asphalt-aggregate ratio. The result of it has been checked by big Marshall method. The pavement performances of ATB mixture have been studied also in this paper, which include mechanical properties, high-temperature stability, and low-temperature anti-cracking performance and fatigue resistance. Through test project, production gradation of ATB was designed and its optimum asphalt-aggregate ratio was determined. Pavement performances of ATB have been checked on field. It has been shown that GTM method was a mixture molding one that approaching actual condition and ATB has fine pavement performances. Finally, the construction method of ATB was studied in this paper. Constructing control requirement and quality warrant measurement was researched, too.