Unveiling the Benefits of Engineered Crumb Rubber for Asphalt Mixtures via Performance-Related Characterization: Rutting Behavior

Engineering Proceedings

article

Usman Ghani¹  Silvia Milazzo¹  Gaspare Giancontieri¹  Chiara Mignini¹  Gabriella Buttitta¹  Fan Gu²  Davide Lo Presti¹ 

[1] Department of Engineering Ed.8, University of Palermo;School of Traffic & Transportation Engineering, Changsha University of Science and Technology

关键词: rutting;    permanent deformation;    performance-related properties;    tire rubber;    modified asphalt mixtures;    AMPT;    ITS;   

DOI  :  10.3390/engproc2023036039

来源: mdpi

【 摘 要 】

Even though alternative paving materials, like rubberized asphalt, are sometimes present in specifications, these are still not widely adopted from road agencies mainly due to a lack of experience, reticence in changing work habits and, often, a lack of evidence of real gains in the change. Authors believe that performance-based laboratory characterization is a solution to highlight differences with conventional asphalt mixtures. Hence, this research wants to highlight the differences between designing asphalt mixtures modified with engineered crumb rubber (ECR) on the basis of conventional indirect tensile testing (ITS), as prescribed by Italian specifications, and by means of performance-related characterization. ECR allows to asphalt mixtures to be modified through a dry process without inconveniences such as uncontrolled swelling and the generation of fumes; on the other hand, performance-related characterization focuses on highlighting rutting behavior by using a basic approach, still based on ITS, and a more advanced viscoplastic methodology using the asphalt mixture performance tester (AMPT). As a result, performance-related characterization is necessary to highlight clear gains in the rutting behavior of the asphalt mixtures modified with ECR. Advanced methodology by means of AMPT provides a fine-tuned characterization; however, the basic approach by means of ITS already highlights the differences in performance. ECR could be widely used to improve the properties of dense mixtures for roads with low traffic; in fact, it solves many of the practical issues of adding crumb rubber through a dry process and greatly improves paving material properties compared to conventional asphalt mixtures, with an increase in cost of only 10%.

【 授权许可】

Unknown