01698392

Component

This study focuses on characterizing the fatigue resistance of asphalt binders subjected to controlled-stress time sweep tests with two objectives. One objective is to propose a failure criterion that defines the true failure, and the other one is to develop a fatigue model that is independent of material types. The ratio of dissipated energy change (RDEC) method and the normalized stiffness ratio (NSR) method are first evaluated with regard to these two objectives. It is demonstrated that both methods fail to define the true failure of asphalt binders, and neither of them provides a fatigue model that is independent of material types. A new failure criterion is then developed through analysis of the three phases of the dynamic shear modulus versus load cycles graph, which defines the true fatigue life as the load cycle corresponding to the second inflection point on such a graph. In accordance with the plateau value (PV) concept utilized in the RDEC method, a new fatigue-related parameter is defined as the RDEC value at the fatigue life determined by the NSR method. Combining the true fatigue life with the new fatigue-related parameter in the form of power function yields a new fatigue model, which is then fitted to the data points of all tested asphalt binders. This new fatigue model is demonstrated to be material type independent. Therefore, the proposed failure criterion is capable of defining the true failure and the developed fatigue model is independent of material types.

This paper was sponsored by TRB committee AFK20 Standing Committee on Asphalt Binders.

19-03200

English

7p

2019

Transportation Research Board 98th Annual Meeting

Digital/other

Figures; References; Tables

Bituminous binders; Fatigue cracking; Shear modulus

Failure criterion; Fatigue life; Fatigue models

Highways; Materials; Pavements

Transportation Research Board Annual Meeting 2019 Paper #19-03200

TRIS, TRB, ATRI

Dec 7 2018 9:23AM