“Additives in Asphalt” was the topic of Association of Asphalt Paving Technologists’ (AAPT) Fall 2018 webinar series. The series consists of three webinars. The first will discuss additives in asphalt mixtures and will provide the foundation for the second and third webinar. The second will delve into the recent developments of how asphalt binder tests have changed, partially because of additives, in order to better understand modified asphalt binder behavior. Finally, the third webinar will explore what is on the horizon for additives in asphalt, including movement toward fundamental characterization through chemistry, sustainability, and engineered design. Note that price of specific additives will not be discussed specifically in this webinar series as the series will focus more on a fundamental understanding of the role of additives in asphalt.

The second webinar in AAPT’s Fall 2018 webinar series, “Additives in Asphalt,” will dive deep into how testing for asphalt binder has changed because of the introduction of additives in asphalt binder. First, the concept of PG+ testing will be explained, which will include a discussion of how the current PG binder grading system may not always be able to properly categorize modified asphalt binders. Next, four tests that are currently being debated and discussed in the asphalt binder expert task group will be reviewed and discussed: MSCR for rutting (AASHTO T350), LAS for fatigue  (AASHTO TP 102), BBS for adhesion/cohesion (AASHTO T361), and low temperature cracking (SENB and Tg). After this webinar, participants should have a working knowledge about how current asphalt binder testing has changed and improved because of the use of additives in asphalt.