![]() ![]() Prepare an initial, or “butter mix” at the design asphalt binder content. Oven-dry the virgin aggregate at a temperature of 230☏ (110☌) and RAP at a temperature of 140☏ (60☌) to a constant mass. Add the lime to the virgin aggregates by making a lime slurry (lime and water mixture) and thoroughly mixing with the virgin aggregates prior to the oven-dry process. Note 2 – If lime is included as a component of the mixture and it has not been previously added to the virgin aggregates, add the appropriate amount of lime per the mix design proportion. Note 1-Include other additives that may be required by the JMF. Obtain samples of asphalt binder in accordance with T 40. Obtain samples of virgin aggregate and RAP in accordance with T 2. Aggregate gradation correction factor-Due to potential virgin and RAP aggregate breakdown during the ignition process, an aggregate gradation correction factor will be determined for each ignition furnace in the location where testing will be performed. ![]() Each ignition furnace will have its own unique asphalt binder correction factor determined in the location where testing will be performed. Such mixes should be corrected and tested at a lower temperature as described A.2.11.1. Asphalt binder correction factor-Certain virgin aggregate types or RAP materials may result in unusually high correction factors (greater than 1.0 percent). ![]() Any changes greater than 5 percent in stockpiled aggregate proportions shall require new correction factors. Correction factor(s) must be determined before any acceptance testing is completed and repeated each time a change in the mix design occurs. Therefore, asphalt binder and aggregate correction factors must be established by testing a set of correction factor specimens for the job mix formula (JMF) containing RAP. Asphalt binder content results may be affected by the type of virgin aggregate and RAP material in the mixture and the ignition furnace. ![]() FLH ADDENDUM TO AASHTO T 308 – Standard Method of Test for Correction Factors for Hot Mix Asphalt (HMA) Containing Recycled Asphalt Pavement (RAP) by the Ignition Method FLH Designation: Addendum T 308 A1. ![]()
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