Application of Cal/apt Results to Long Life Flexible Pavement Reconstruction

The California Department of Transportation (Caltrans) needs to rehabilitate or reconstruct much of its network of urban freeway pavements. A strategy has been developed by the Caltrans Accelerate Pavement Testing (CAL/APT) program to reconstruct these pavements with a flexible pavement incorporating design features that minimize the thickness of the pavement and improve constructability. The strategy meets Caltrans objectives for " Long-Life Rehabilitation Strategies " of 30 years service life and minimum maintenance. This paper describes the strategy and discusses validation and calibration analyses based on accelerated pavement testing using the Heavy Vehicle Simulator, laboratory tests, and mechanistic-empirical analyses. Elements of the strategy evaluated include use of a " Rich Bottom " asphalt concrete layer with enhanced fatigue properties, improved compaction of the asphalt concrete, use of rut resistant mixes in the critical zone for mix rutting, and subgrade rutting criteria. An example design is presented in the paper. Harvey et al.