Florida I-95 Rehabilitation
Jul 17, 2013
The European Roads Review's Fall 2012 – Spring 2013 issue details Hubbard's rehabilitation project on I-95 last year that compared the performance of WMA to HMA. Working with the Florida DOT, the project evaluated the performance of a Superpave 12.5 mm mix incorporating 30% RAP. Neither the hot mix control nor the Evotherm mix utilized an adhestion promotor. Evotherm is now an approved liquid antistrip in Florida.
Hubbard Group's Taft asphalt plant in Orlando, Florida, produced the mixes at 200 tons/hour. HMA was produced at 325-340 F while Evotherm WMA was produced at 230-240 F. At the jobsite, the Evotherm asphalt mix was delivered at an average temperature of 224 F compared to 316 F for traditional hot mix. These temperature reductions of up to 100 Fahrenheit degrees provided multiple benefits:
- 23% lower fuel consumption
- 30% lower particulate emisssions (TPM)
- 48% lower NOx emissions
- Field densities from 92.5% to 93.5%
- Improved work environment (Florida gets hot!)
Back at the QC lab, tests on core samples showed that the WMA resistance to water damage was comparable to the HMA reference. To complement the laboratory analysis, a series of infrared thermographic photos were taken during the field placement operations. Shown below, they clearly illustrate the lower and more consistent temperature profile obtained when using Evotherm WMA and that lead to a higher quality asphalt paving job.