Evaluation of Recycled Asphalt Concrete Materials as Aggregate Base

This technical memorandum summarizes the evaluation of a rehabilitation strategy that involves recycling an existing asphalt concrete surface and a portion of the base material into a new base layer. A series of field and laboratory tests were conducted to evaluate this rehabilitation strategy. Field tests included destructive and non-destructive testing conducted on a pavement section located on California State Highway 395 between PM 13 and PM 10, which is about 10 miles south of Alturas, CA. For purposes of analysis and discussion, the starting station is 0.0 (m) at PM 13 and the ending station is 4800.0 (m) at PM 10. The recycling process was conducted between stations 0.0m and 3125.0 m. Laboratory tests included static and dynamic tests on the recycled asphalt concrete and two California aggregate base class 2 materials.The objectives of the study are1) to evaluate the performance of the recycling process in the field by analyzing destructive and non-destructive data before and after the recycling process2) to characterize the recycled asphalt concrete material under standard and triaxial laboratory tests3) to compare the laboratory performance of the recycled material with typical California aggregate base class 2 materials. Based on the results, recommendations are given to Caltrans on the use of recycled asphalt concrete materials.