Evaluating Pavement Condition of the National Highway System

FHWA recently conducted a study to identify a means for evaluating the health of the Interstate highway system, with a specific focus on pavements and bridges. One important component of any statement of health is the condition of the pavement, which is the focus of this paper. Data on an 874-mi long corridor of 1-90 were used to review the potential of a set of six metrics for evaluating pavement condition as good, fair, or poor across the Interstate network. The metrics reviewed included both functional and structural pavement condition. The study concluded that currently the international roughness index provides the most consistent method for evaluating ride quality. Other metrics, which use distress or structural condition to evaluate pavement, are not currently suitable as measures of nationwide condition and will require further work before they can be implemented for routine use.