Guidelines for evaluation of highway pavements for rehabilitation

This paper presents an overview of the project-level evaluation process described in the Guide for Selection of Pavement Rehabilitation Strategies, developed under NCHRP Project 1-38. The guidelines for pavement data collection address pavement section inventory, traffic analysis, distress surveying, nondestructive deflection testing, materials sampling and testing, profile and roughness measurement, friction measurement, drainage inspection, and other nondestructive testing. The guidelines for project-level pavement evaluation address distress evaluation, structural evaluation, and functional evaluation, drainage evaluation, and identification of uniform sections. Trigger values are suggested for key condition levels at which a pavement is generally considered to need a structural improvement. Similarly, trigger values are suggested for key condition levels at which a pavement is generally considered to need a functional improvement. The results of the distress, structural, functional, and drainage evaluations lead directly into the selection of appropriate rehabilitation techniques for each of the three main pavement types considered, combination of the individual rehabilitation techniques into one or more feasible rehabilitation strategy alternatives, life-cycle cost analysis of the alternatives, and selection of a rehabilitation strategy.