Abstract:
This paper presents a method of engineering economy analysis for estimating the average daily traffic (ADT) volume at which it is economical to improve low-volume gravel roads. Based on alternative roadway crossectional designs, total equivalent uniform annual transportation costs for a 15-year analysis period are calculated as a function of ADT. These costs are plotted as the dependent variable versus traffic as the independent variable. The plots show ADT levels at which it is economical to change from the use of one roadway design to another. The analysis is one part of a comprehensive study conducted in 1972 by the Military Traffic Management Command in coordination with the U.S. Air Force and the Federal Highway Administration. The report was initiated to review a proposal by the North Dakota State Highway Department (NDSHD) to improve public roads used by Minuteman intercontinental ballistic missile transporter-erector vehicles in the vicinity of Minot Air Force Base. NDSHD supplied alternative roadway designs, roadway cost data, and traffic data. The Air Force supplied military traffic data. Unit costs for vehicle operation, motorists' time, accidents, and other factors were considered and obtained from FHWA and the literature. Because of recent inflationary price trends, the analysis is relatively more important for its methodology than for its findings.
Supplemental Notes:
Proceedings of a work shop held June 16-19, 1975, in Boise, Idaho by the Transportation Research Board.
