Florida APT Update
Current APT Research Asphalt segregation Tack coat rate effect on cracking resistance Asphalt density FC-5 thickness High polymer binder
Asphalt Segregation Impact of segregation on pavement performance Develop/refine methods to quantify segregation using texture measurements (CTM) Finalizing report
Asphalt Segregation
Tack Coat Rate Inadequate tack coat may increase top-down cracking potential Three residual tack coat rates 0.02 gal/sy, 0.04 gal/sy, & 0.06 gal/sy One unbonded section
Asphalt Density Three densities were targeted 87%, 90%, and 93% Establish guidelines for inspectors
FC-5 Thickness Thicker open-graded friction courses ravel & rut quicker FC-5 placed at 0.75, 1.25, and 2 inches thick PG 76-22 & PG 82-22 binders 1.5-inch SP-12.5 w/ PG 76-22 10.5-inch limerock base 12-inch granular subbase FC-5 Variable thickness
High Polymer Binder PG 76-22 HP vs. PG 76-22 rutting & cracking comparison Two binder contents for PG 76-22 HP Design AC content Design AC content + 0.5%
Concrete Test Road Two construction phases Phase 1 Phase 2 Earthwork Instrumentation infrastructure Work began Nov 1 Phase 2 Concrete paving Scheduled to let July 2018 More details http://www.fdot.gov/materials/pavement/research/reports/stateroad/301.pdf