Development of Peak-Hour and Peak Directional Factors for Congestion Management Systems

Abstract

A statewide congestion management system involves the application of large amounts of traffic data to a large number of roadway links at a detailed level. A procedure has been developed to identify congestion on roadway links at a macroscopic level using daily volume counts. Daily volume counts are used to determine a.m. and p.m. peak-hour (K) and peak-directional (D) factors. These factors are then used with average daily traffic data to determine whether a link is congested at a preliminary level and in need of further analysis. Links identified as congested can then be subjected to a more detailed microscopic study using hourly volume counts to determine extent, duration, and severity of congestion. Development of a.m. and p.m. K and D factors for five different classes of roadways is discussed and values that can be used in congestion management systems are recommended.