Although still very young, the SHRP Long Term Pavement Performance (LTPP) studies are making significant progress toward each of the objectives set forth in the research plans laid by the AASHTO SHRP Task Force in 1986. This progress will be reflected in changes to the AASHTO Guide for Design of Pavement Structures at the time of its next revision, probably around 1995. This paper focusses on the LTPP derived amendments to the guide which will include: 1) newly calibrated design equations; 2) improved procedures for rehabilitation; 3) predictive equations for specific distresses; 4) improved materials characterization; 5) guidance on productive construction quality control activities; 6) new techniques for traffic characterization. Taken individually, each of these potential revisions would greatly impact real pavement performance or our ability to more accurately predict that performance. (A)
Abstract