Estimation of design hourly volume from seasonal traffic counts

Abstract

By considering the 30th highest hourly volume (30HV) as the design hour volume, this study reexamines a commonly used method of predicting the 30HV as a function of the annual average daily traffic (AADT) volume. Based on Alberta's highway system data, some common limitations of the traditional 30HV-AADT model are pointed out. Also included in the analysis presented is a proposed alternative model which utilizes July/August traffic data to estimate the design hour volume. The alternative model appears to provide more accurate prediction results and it also eliminates the need of subjectively classifying the roads into various groups as required by the 30HV-AADT method. -Authors