LTRC Secures Contract from Shell for Thiopave Testing

June 5, 2010

The Louisiana Transportation Research Center (LTRC) was awarded a contract from Shell Oil Company to characterize the laboratory performance of conventional HMA mixtures and mixtures containing Thiopave additives through their fundamental engineering properties. After participating as a guest lecturer at the Southeast Asphalt User Producer Group, Shell employees approached Engineering Materials Characterization Research Facility (EMCRF) Manager and LSU Civil Engineering Professor Louay Mohammad, Ph.D., with a unique concept that has the potential to replace a large percentage of the asphalt cement currently used to produce asphalt mixtures for roads by utilizing Shell Thiopave additives. The main focus for this particular research involves infrastructure sustainability.

"The goal is to be able to produce mix at lower cost without compromising performance by using innovative material selection and mixture and pavement structural design," said Mohammad. "Thiopave has the potential to save Louisiana money and improve roads' performance by lowering the cost of necessary materials since Shell Thiopave can replace up to 40 percent of the asphalt cement, which is more expensive and rises in cost parallel to crude oil."

Mohammad also explains that by replacing a portion of the asphalt cement in the asphalt mix with Shell Thiopave, the overall mix strength may increase, resulting in an improved load-bearing capacity of finished roads and, therefore, exceeding service life. Another potential impact of using Shell Thiopave is that it can help

reduce energy requirements at asphalt plants. Shell Thiopave is an additive containing sulphur that enables lower temperature production, using less fuel, thereby delivering meaningful reductions in greenhouse gas emissions. This proves to be an advantage for the state of Louisiana, which contains several non-attainment areas that struggle to meet the strict air quality standards.

In addition, Mohammad is in the process of securing additional work for Shell to carry out his testing in a larger scale at LTRC's Accelerated Loading Facility (ALF).

Article excerpted from Louisiana Transportation Research Center publication "Technology Today"