The Indiana Department of Transportation (INDOT) announced a significant change in asphalt binder specifications in 2024, transitioning from PG 64-22 to PG 58-28. This change, effective for contracts let on or after September 1, 2024, affects all base grade liquid asphalt binder in Indiana as well as the testing requirements (from AASHTO M320 to AASHTO M332, incorporating AASHTO R92 requirements). In addition, the terminology of which liquid asphalt binders are referred to will be updated to align with these changes.
Why the change?
According to Asphalt Pavement Association of Indiana, the primary goal of this specification change is to enhance the durability and quality of asphalt pavements to increase pavement life in Indiana. The adoption of PG 58-28 is set to better represent the high and low temperature extremes experienced across the state.
How we’ve prepped
At Asphalt Materials, Inc. (AMI), we have been diligently preparing for this transition since learning about the INDOT specification change. This shift requires a significant modification to our asphalt supply, particularly in how we blend performance grade Multiple Stress Creep Recovery (MSCR) grades.
To address this, AMI collaborated with the Heritage Research Group (HRG) to explore available options for creating these new asphalt blends. Collaborating across departments with the Supply, Operations, and Sales teams, the Engineering Department proposed a new storage plan and developed an automated asphalt blender system to enhance efficiency and reliably produce the new specification blends. The team tested the blender system in full tanker trucks to ensure the new equipment and instrumentation performed consistently and produced in-specification blends in preparation for the upcoming season.
Kit Peregrine, QA/QC Manager, highlights the significance of this collaboration: “We started working on this project early and with a team effort between AMI Engineering, HRG, and our Indianapolis plant, we’re set up to succeed as this new change is rolled out.”
The dedication and hard work of Tim Reece (Chemical Research Scientist, HRG) and Mitch Kovalsky (Senior Project Engineer, AMI) have been instrumental in this project’s success. Their efforts ensure that AMI is well-prepared to meet the new INDOT specifications and continue delivering high-quality asphalt products to our customers.
Ready for any challenge
One of AMI’s strengths lies in our collaboration with our comprehensive lab network and family of Heritage companies. These partnerships equip us with the technical expertise and flexibility needed to quickly adapt to meet the evolving demands of the industry. With our dedicated team at-the-ready, we’re positioned to thrive when our customers need us most.
Do you have questions about the INDOT PG 58-28 spec change or how we’ve prepared? Reach out, we’d love to chat [email protected]
