University of California Pavement Research Center

This report is one of a series detailing the results of the CAL/APT program, a research effort being performed jointly by the University of California, Berkeley Pavement Research Center and the California Department of Transportation (Caltrans). It contains an evaluation of the performance of asphalt treated permeable base (ATPB) in asphalt concrete pavements based on observation, laboratory testing of ATPB, and computer simulation of representative pavement structures. The evaluation includes: 1) a summary of Caltrans experience with ATPB and drainage systems relative to their development and implementation, together with observations of field performance with respect to maintainability and stripping of asphalt treated materials; 2) a summary of the characteristics and performance of ATPB materials and drainage systems used by two other highway agencies; 3) results of laboratory investigation of the stiffness and permanent deformation characteristics of ATPB mixes, including the effects of soaking and loading while saturated on these parameters; and 4) the results of analyses of representative pavement structures to quantify the expected effects of as-compacted and soaked ATPB on pavement performance.