In many countries, particularly in the developing world, a largepercentage of the road network is made up of gravel roads. Although such roads are suitable for low traffic volumes, many countries have had rapid increases in traffic levels. This process has resulted in large expenditure on maintenance and rehabilitation of gravel roads as well as high costs of vehicle operation. At high traffic levels, it is therefore desirable to upgrade such roads with bitumen or asphalt pavements to reduce total costs. A computer package incorporating the world bank highway design and maintenance standards model (hdm-iii) has been developed to determine the traffic levels at whichit becomes economical to upgrade road pavements. Depending on the level of accuracy required, the computer package may be used to give approximate or detailed results. At the simplest operation level, only a few data variables are required to accomplish a quick analysis giving approximate results. A graphical plot of the total costs is displayed on the computer screen showing the crossover point at whichupgrading becomes viable. This paper appears in transportation research record no. 1291, Fifth international conference on low-volume roads, may 19-23, 1991, raleigh, north carolina, volume 1.
Abstract