Pavement Roughness and Rideability Field Evaluation

This report summarizes the work performed to develop transforms between subjective appraisals of pavement rideability and profile measurements of pavement roughness. The goal of the study was to verify the form and accuracy of the transform developed in NCHRP 1-23, based on data from one state, by extending the methodology to four additional states. Panel rating studies were conducted in NJ, MI, NM and LA and panel rating data and profiles were collected on 282 pavement sections. Statistical analyses were used to develop transforms between the physical profile measurements and the subjective panel ratings of rideability, between Mays Ride Meter measurements and the panel ratings and between the panel ratings and subjective appraisals of a pavement's need for repair. In addition, the effects of surface type, road class, vehicle size, panel residence or regionality and alternative models of profile roughness were determined. The major results of this study were that the transforms that predict subjective appraisals of rideability from profile measurements of pavement roughness are accurate and valid over an extremely wide range of roughness and that the preferred transforms, based on the combined data from all five states, can be used to predict rideability for any paved surface. They provide a basis for a system of measuring and reporting totally comparable rideability or roughness data that can also be used to assist highway agencies to determine when existing pavements should be repaired and to evaluate newly constructed pavements.