SERVICEABILITY RATINGS OF HIGHWAY PAVEMENTS

Abstract

THERE IS A NEED FOR A SIMPLE, ACCURATE AND ECONOMICAL METHOD OF EVALUATING PAVEMENT SERVICEABILITY. THE USE OF RATING PANELS TO MEASURE THE PRESENT ADEQUACY OF A HIGHWAY PAVEMENT WAS STUDIED EXPERIMENTALLY AND THE RESULTS WERE ANALYZED STATISTICALLY. IT WAS FOUND THAT THE PANEL METHOD OF EVALUATING PAVEMENT SERVICEABILITY IS PRACTICAL, IS APPLICABLE TO RIGID, OVERLAY AND FLEXIBLE PAVEMENTS, AND MINIMIZES THE VARIATION AND PERSONAL BIAS INVOLVED WHEN PAVEMENT MAINTENANCE AND RECONSTRUCTION PRIORITY PROGRAMS ARE DETERMINED ON THE BASIS OF THE KNOWLEDGE AND JUDGEMENTS OF INDIVIDUALS. RATINGS BETWEEN INDIVIDUALS VARIED WIDELY, REGARDLESS OF THE EXTENT OF THEIR HIGHWAY EXPERIENCE. RATINGS BY PANELS, HOWEVER, DO NOT VARY WIDELY AND ARE GOOD ESTIMATES OF THE PRESENT SERVICEABILITY OF HIGHWAY PAVEMENT SECTIONS. KNOWLEDGE AND EXPERIENCE IN THE HIGHWAY ENGINEERING FIELD IS NOT IMPORTANT IN SELECTING PANEL MEMBERS. THE RELATIONSHIP BETWEEN PANEL SIZE AND RATING ACCURACY IS PRESENTED. THE ROUGHOMETER METHOD OF EVALUATING PAVEMENT SERVICEABILITY WAS ALSO STUDIED. WHILE SIMPLE AND OBJECTIVE, IT WAS FOUND TO GIVE EXCELLENT CORRELATIONS TO THE JUDGEMENT OF THE TRAVELING PUBLIC WHEN USED ON RIGID PAVEMENTS, BUT ONLY FAIR CORRELATION ON FLEXIBLE AND OVERLAY PAVEMENTS.