Evaluation of Warm Mix Asphalts with High Reclaimed Asphalt Content

The present chapter provides a synthesis of the research activity of RILEM TC 264-RAP Task Group 2 (Performance of Recycled As-phalt Mixtures Manufactured at Lower Temperatures). The study fo-cused on evaluating the mechanical performance of asphalt mixtures incorporating 40% reclaimed asphalt (RA) and produced using warm mix asphalt (WMA) technologies. This chapter is structured into six sections. First, an abstract is provided, followed by a detailed moti-vation (Section 2), outlining the need for the study. Section 3 pro-vides a comprehensive background on WMA technologies and their integration with RA, supported by a detailed literature review. Sec-tion 4 summarizes the literature findings, emphasizing performance variability and research gaps. Section 5 describes the materials and methodology of the inter-laboratory testing program involving six in-ternational laboratories, including mix design choices, material char-acterization, and testing protocols. Section 6 presents the results of the mechanical testing campaign, covering compactability, moisture susceptibility, rutting, modulus, and fatigue performance. Finally, Section 7 concludes the chapter with key insights and recommenda-tions for practice, emphasizing the importance of reliable RA charac-terization, binder selection, and long-term field validation. Overall, the findings emphasize the potential of WMA+RA mixtures for achieving better performance and sustainable growth.