Disruption factor of asphalt mixtures

Abstract

Typically, aggregate gradation is selected to meet Superpave mix design specification; however, many Superpave mixtures have exhibited deficient field performance. The porosity of the dominant aggregate size range (DASR), which is the primary structural network of aggregates, has been extensively validated as a tool to evaluate coarse aggregate structure of laboratory and field asphalt mixtures. Mixtures identified by the system as having poor or marginal gradations resulted in poor rutting resistance. This study focused on how asphalt mixture performance is affected by changes in interstitial component (IC), which is the material between DASR particles. Laboratory testing clearly showed that IC characteristics may have a significant effect on rutting and cracking performance of mixtures. The disruption factor (DF) was developed to evaluate the potential of IC aggregates to disrupt the DASR structure. DF satisfactorily distinguished poor performing mixtures; therefore, it may eventually be used in combination with DASR porosity as a design parameter for rutting and cracking resistant asphalt mixtures.

Keywords:

• aggregate
• gradation
• asphalt
• DASR
• disruption
• performance

Acknowledgements

The authors would like to acknowledge and thank the Florida Department of Transportation (FDOT) for providing technical and financial support and materials for this work. Special thanks go to engineers and technicians of the Bituminous Section of the State Materials Office, in particular to Mr Gregory A. Scholar and Mrs Shanna Johnson, for their contributions in terms of their expert knowledge, experience and valuable assistance in the laboratory testing for this project. Their efforts are sincerely appreciated and clearly made a positive impact on the quality of the research.

Notes

^1. Current address: KTH Royal Institute of Technology, Division of Highway and Railway Engineering, Stockholm, Sweden.

^2. [email protected].

^3. [email protected].

^4. [email protected].

Additional information

Notes on contributors

Alvaro Guarin

1

Reynaldo Roque

2

Sungho Kim

3

Okan Sirin

4