Determining accurate asphalt content of mixtures is critical, particularly as the quantity of recycled materials allowed during production increases. TRB hosted a webinar on Wednesday, February 28, 2024 from 11:00 AM to 12:30 AM Eastern that presented the work conducted by NCHRP to revise the current AASHTO T 308 test procedure to be able to incorporate mixes with high recycled materials content. Presenters explored the effect of reducing the test temperature from 1,000 degrees Fahrenheit to 800 degrees Fahrenheit. Presenters also shared a new precision statement of the AASHTO procedure including recycle mixes.

This webinar was based on NCHRP Research Report 1060: Ignition Furnace Correction Factors: Identifying Influences and Minimizing Variability.

This webinar was sponsored by TRB’s National Cooperative Highway Research Program.

The slides are linked in the meeting materials. View the recorded webinar below.

Webinar agenda and presenters

1. Limitations of AASHTO T 308 – Ray Brown, National Center for Asphalt Technology

2. Report summary – Carolina Rodezno, National Center for Asphalt Technology at Auburn University

3. Question and answer session moderated by Roberto Barcena, Transportation Research Board

The first 60 minutes of the webinar were for presentations and the final 30 minutes were reserved for audience questions.

Learning Objectives

At the end of this webinar, participants can:

1. Identify the current limitation of AASHTO T 308 for asphalt content determination of mixes with high recycled materials

2. Make modifications to AASHTO T 308 procedure for more accurate asphalt content determination

3. Apply the revised precision statement of AASHTO T 308

Professional Development Hours

This webinar was delivered as a scheduled – e-learning live event and is categorized within RCEP as Technical, Health and Safety.

Professional Development Hours (PDHs) earned on completion of this program were reported to the Registered Continuing Education Program (RCEP). Certificates of Completion are issued to all participants via the RCEP.net online system. Complaints about registered providers may be addressed to RCEP, 1015 15th Street, NW, 8th Fl., Washington, DC, 20005.