Over the last 5 years, maintenance management systems for unpaved roads, such as the maintenance and design system and highway design and maintenance system, have become increasingy available. Detailed data requirements have, however, deterred many potential users from implementing these systems, especially for low-volume roads. Furthermore, these systems are based on deterioration relationships obtained from a study in brazil, and the applicability to other areas hasnot been confirmed. Therefore, local relationships with good predictability and low data requirements needed to be developed. During a recent study in southern africa, a new set of relationships was developed for the prediction of roughness deterioration and gravel loss for low-volume unpaved roads over time. These relationships are muchsimpler than the previous ones, thus fulfilling local needs. The new relationships were compared with the existing models. The effects of the different models on management decisions about annual gravel replacement were examined by comparing the results of each model as it evaluated a typical unpaved road network. The blading frequency was evaluated by the blading cost and total cost, including vehicle operating costs. On the basis of these findings, conclusions about the potential necessity for upgrading can be drawn. Road authorities worldwide must consider the applicability of models developed in one environment to other environments and the potential impact on management decisions. This paper appears in transportation research recordno. 1291, Fifth international conference on low-volume roads, may 19-23, 1991, raleigh, north carolina, volume 2.
Abstract