Among the many parameters that influence the selection of maintenance strategies for unpaved roads, two factors have been selected in this paper to illustrate that caution needs to be exercised when attempting to transfer policies or standards from one set of conditions to another. These two factors are factor costs (not budgets) and material resources. Broadly speaking, the definition of a maintenance policy for an unpaved network implies that besides routine activities such as vegetation control and ditch and culvert cleaning, consideration should be given to the frequency of grading and also to the timing of graveling operations. Drawing from the experience collected in two widely different environments, one in the equatorial forest region of central Africa - where maintenance costs are high and gravel resources scarce - and the other in northeast Brazil, it is shown that maintenance standards are highly dependent not only on traffic volume but also on the properties of surfacing materials and the unit cost of grading.
Abstract