Dr. Tom Scarpas, head of pavement engineering at Delft University of Technology, Netherlands, was this year’s Kent Distinguished Lecture presenter.
In his presentation on March 20, “Rejuvenation of Asphalt Mixes: Turning Back the Clock,” Scarpas discussed research he and his colleagues in the Netherlands are pursuing to reverse stiffening that occurs in bituminous paving as it ages. The Netherlands, like the United States, is dealing with an aging infrastructure. Rather than focusing on how to design and build new pavements, Scarpas and his research team were charged with determining methods for increasing the service life of existing pavements. As part of that research, they investigated additives known as rejuvenators, which can be applied to bituminous pavements to restore functional properties to aged binder.
Not unlike human skin, bituminous pavement tends to oxidize, or lose oxygen, as it ages.When Scarpas and his research team were investigating how to best rejuvenate pavement, they reached out to cosmetics giants, such as L’Oreal, that are famous for their aging-reversal skin creams. Their objective was to determine the chemistry behind what turns back the clock for aging skin to determine whether similar additives could do the same for aging pavements.
These rejuvenators are applied to pavements at night via spreaders and are allowed to seep through the pores. Air is then blown onto the treated pavement to push rejuvenators further into the surface. After that is done, the pavement is covered with a surfacing component. The entire process takes about 90 minutes, which means minimal downtime on the roads.
The research has yielded strongly positive results thus far, and Scarpas explained that his team is also examining how rejuvenators can be used on pavements that have already been scrapped so that they can be recycled to build new roads.
Scarpas holds a Ph.D. in civil engineering from Delft University, an M.S. in civil engineering from the University of Canterbury in New Zealand, and a B.S. in civil engineering and applied mechanics from McGill University in Canada. His research interests include constitutive modeling and testing of pavement engineering materials, chemo-mechanics, and computational mechanics. He is chairman of the Technical Committee on Constitutive Modeling of Asphalt Pavements of the International Society of Asphalt Pavements and is active on several RILEM and TRB committees. He serves as co-editor in chief for the International Journal of Pavement Engineering.
The Paul Fraser Kent Memorial Lecture, initiated in 2007, honors outstanding leadership in the field of transportation engineering. Kent was a 1920 graduate of the University of Illinois in civil engineering. As a highway contractor and materials supplier, he owned and operated two Champaign-based companies, General Paving and Builders Supply. Throughout his professional career, he expressed the highest regard and great esteem for the education in civil engineering he received at the University of Illinois. Kent dedicated himself to civic service in Illinois and surrounding states. He was the founder and president of the University of Illinois Civil Engineering Alumni Association and was the recipient of the U of I Loyalty Award and the Civil Engineering Distinguished Alumnus Award. The Kent Distinguished Lectures are sponsored by the Paul F. Kent Memorial Fund, established in 1977.