Predicting Directional Design Hourly Volume from Statutory Holiday Traffic

Estimating design hourly volume (DHV)—commonly the 30th highest hourly volume (30HV) in a year—from sample counts is an important aspect of traffic engineering practice. Directional DHV (DDHV) on highways without permanent traffic counters (PTCs) is usually determined by the estimated annual average daily traffic (AADT) being multiplied by the ratio of DHV to AADT and the directional split ratio during the DHV at a PTC on a similar road. However, highway designers have questioned the validity of this method, and its limitations have been well discussed. Because recreational travel on most holidays in developed countries is active and increases highway traffic volumes vastly, the main intent is to develop more accurate and efficient DDHV prediction models based on directional hourly volumes that occur during holiday periods. The existing literature on DHV is reviewed, then holiday traffic peaking characteristics are investigated on the basis of the past 20 years of data from PTCs on rural highways in Alber...