Study of the Influence of the Variability of Traffic-Related Parameters on the Service Life of Flexible Pavement Structures in Senegal by a Mechanistic-Empirical Approach

The results of the study showed that exceeding the axle load and axle configuration are indisputably among the most damaging factors for flexible pavement structures in Senegal, made of local materials (Diack basalt, Sindia laterite). The regulatory axle load recommended by UEMOA for users is set at 11.5 tons and 12 tons for a single and twin axle respectively. For calculation purposes, this load is set at 13 tons. However, in Senegal, this axle load is often exceeded, and given the diversity of heavy goods vehicles in traffic, single axles, whose effects, according to several authors, are more detrimental to flexible pavement structures, are increasingly observed in road traffic. Differences in fatigue cracking and rutting damage between single and dual wheels, as well as load overruns, show the need to take axle configuration and possible overloads into account when dimensioning flexible pavement structures in Senegal, and when planning their maintenance, the costs of which are excessively high, according to Senegal's Autonomous Road Maintenance Fund (FERA). Keywords: Single wheel, dual wheel, damage, fatigue cracking, rutting, traffic