Now a day than it was before road pavement damage associated with vehicle overloadingrnparticularly from those heavy vehicles are becoming increasingly threatening in Ethiopia. Mostrnof the road pavements constructed since the last 10-15 years are deteriorating much before theirrnuseful design life (period) and are calling for early overlay if not for complete reconstruction.rnThis is mainly associated with the growing economy of the nation and associated increase inrntransport demand. The ever growing demand in transport in turn calls for an effective transportrnsystem. One way of achieving this is currently manifested by introduction of heavy trucks andrntruck trailers for transporting goods. Although this is a normal trend in growing economies therndamage that these vehicles induce on flexible bituminous surfaced roads is intensified byrnexcessive overloading exceeding the permitted axle load limits.rnWith this in mind and to study the effect of overloading and the role of axle load regulations thernresearch therefore focused on the following two objectives:rnâ€¢ How does vehicles overloading affect the pavement service lifernâ€¢ Role of axle load enforcement or regulationrnAccordingly the road segment from Adama to Awash is selected for this study. The Adama -rnAwash road as part of the main import-export Highway is carrying a considerable amount ofrntruck and truck trailers travelling to and from the port of Djibouti. Furthermore it also servesrntraffic that are coming and going to the eastern part of the country mainly joining the port trafficrnat Awash.rnDespite a pavement with thick asphaltic layer currently the asphalt concrete is intensively andrnextensively cracked. It is heavily deformed with extreme undulation and deep rutting to thernextent of causing traffic hazard at a number of places particularly along climbing lanes. This isrneven worst starting from the town of Wolenchiti to that of Metehara and near the Awash bridgerncrossing where the route corridor is characterized by several ups and downs with high day timerntemperature (hotter climate). Therefore it is considered to set a very good example for thernadverse effect of overloading in line with the core objective of this research.