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22 performed on the HMA control and WMA mixtures produced the Phase II studies. The final modifications are discussed using Advera, Evotherm, and Sasobit. All mixtures used PG 64- in detail in Chapter 3. The mixture design portion of the 22 binder. The HMA mixture was prepared at the recom- revised preliminary procedure was reformatted to be in mended viscosity-based mixing and compaction temperatures. the form of an appendix to AASHTO R 35 highlighting spe- The WMA mixtures were prepared at the midpoint of the tem- cial mixture design considerations and procedures for ad- peratures used in the mix design experiment. After com- dressing WMA during mixture design. This document is paction, all specimens were long-term oven aged in accordance included in Appendix A of this report. Appendix B is a with AASHTO R 30 to simulate the effects of long-term aging. commentary that provides supporting information for use The data from the study were evaluated to determine whether in adoption and future revision of the mix design consid- the fatigue characteristics of WMA mixtures are significantly erations and methods for WMA. Training materials for in- improved over HMA mixtures. troducing the recommended WMA methods are included in Appendix C. The mixture analysis portion of the proce- dure was reformatted to be a standard practice for measur- 2.7 Draft Standards for WMA ing properties of WMA for performance analysis using the The mixture design portion of the revised preliminary MEPDG (1). This proposed standard practice is included in procedure was further modified based on the findings of Appendix D.