Florida DOT
Florida has a couple of changes to specifications coming into effect in July 2024.
First, contractors will have the option to apply a prime coat to the base layer if the base is completed or final prepped within 24 hours of paving. They must ensure the base moisture content is within an acceptable range, the base must be protected from rain, and it must adequately bond to the new lift of asphalt pavement.
Second, in the mix design approval process, if the contractor’s mix design fine aggregate angularity (FAA) fails (less than 45.0) and falls between 42.0 and 45.0, they can opt to test samples in the Asphalt Pavement Analyzer (APA). If the rut depth is 4.5 mm or less, the failing FAA value will be waived.
Ohio DOT
We revamped our balanced mix design benchmarking for 2024. We’re aiming to collect short-term (R 30) and long-term (using the new Method D AASHTO standard) for IDEAL-CT and Hamburg (rutting and moisture susceptibility) tests, alongside some 3-wheel polishing on select projects for mix design.
We’re also planning to collect production mix for creating hot-compacted pills and reheating mixtures to run IDEAL-CT and HT-IDT tests (as per ALDOT 458). We’re planning test section trial projects based on the CAPRI Guidelines and Recommendations for Field Validation of Test Criteria for BMD Implementation report.
Furthermore, a rutting research project began in January to establish criteria for Hamburg testing and determine a rapid rutting test for QA with criteria based on field data.
We plan to fully implement PWL on core densities in 2026, following successful pilot projects from 2023 to 2025.
We’re also exploring the potential implementation of paver mounter thermal profiling on projects, as we’ve conducted numerous shadow projects over the past decade.
Utah DOT
UDOT is transitioning towards using the HiMod binder, specifically PG 76-34, for our dense graded HMA. This shift aims to achieve better density and durability by increasing our binder contents without the risk of rutting.