AUSTIN, Texas—Adding waste toner to make highway asphalt more durable earned two University of Texas at Austin engineers a place on the Texas Department of Transportation (TxDOT) list of Top 10 Research Findings or Innovations for 2000. The award is based on “substantial current and future value to the Texas Department of Transportation and the taxpayers of Texas.”
Dr. Thomas Kennedy, professor of civil engineering, and Dr. Mansour Solaimanian, research engineer in civil engineering, received the award for their extensive study of the use of waste printer toner in asphalt and asphalt pavements.
Waste toner occurs as a by-product of the manufacturing process as well as residue from copiers and printers. Typically, it has been deposited in landfills for lack of a viable recycling alternative. An inert product, it contains more than 80 percent co-polymer and 5 percent to 10 percent carbon black.
The researchers discovered that this waste product, in fact, builds more durable roadways, saving both road construction and maintenance costs.
The two UT Austin investigators initially were examining the influence of waste toner on the high temperature engineering properties and performance of asphalt mix concrete under laboratory conditions. This research earned them the Better Roads’ Outstanding Transportation Research Award in January 1997.
In their first large-scale trial in August 1997, approximately 25 tons of waste toner was shipped to Waco from two toner-manufacturing plants. It then was blended with binder at a local hot mix plant facility. More than 5,000 tons of asphalt paving containing the toner-modified binder subsequently were applied as an overlay to a two-kilometer stretch of Loop 396 (Valley Mills Drive).
This six-lane road commonly experiences a relatively heavy and slow-moving truck load and also had been experiencing considerable, lasting deformation at intersections prior. Since the new product was applied, however, the road has survived three summer/winter cycles in excellent condition, researchers found.
The project’s success has led to a joint UT Austin-TxDOT patent insuring the availability of the process for Texas highways and streets.
Kennedy, head of the asphalt program in civil engineering at UT Austin, was lauded last year with the Association of Asphalt Paving Technologists’ Honorary Membership for Outstanding Eminence in Asphalt Technology. A member of the engineering faculty since 1965, he holds the Engineering Foundation Professorship in Civil Engineering.
Solaimanian is a registered professional engineer who received his doctorate in civil engineering from UT Austin in 1990.
For more information, call Becky Rische at the UT Austin College of Engineering at (512) 471-7272 or Rae Nadler-Olenick at (512) 471-7541.