Results of surface hot-in place recycling (remix) of modified and alternative asphalt mixtures in Finland. Part II: bitumen scale

Surface hot-in place recycling of asphalt mixtures has been conducted on Finnish roads for several years. The procedure is performed either in full-lane('remix') or shorter widths ('rut-remix'). In a 2020-2021 project, different mixture types were subjected to both kinds recycling; reference mixtures, and modified with aramid fibres, FEP elastomer pellets, polymer, Storelastic rubber additive, recycled shingles, steel slag, soft bitumen. This paper (Part II) presents the results an extensive laboratory test plan at bitumen scale. Asphalt cores recovered from four roads, was extracted fortesting. Various tests bitumens original state (aged, before recycling) after (remix rut-remix), including FT-IR, DSR, MSCR, as well content, penetration, softening point. master curves constructed all bitumens. Gradations are also presented herein. effect remix/rut-remix evaluated via changes measured properties (including Glover-Rowe) recycling, over wide range temperatures. complement mixture-scale data provide comprehensive database performance extended group materials. Data appendices accessible link bottom page.