Kokoro Kobori¹, Doua Allain Gnabahou^1,, B. Kossi Imbga¹, Vincent Sambou²

The multiplication of heavy vehicle axles is a growing phenomenon in the WAEMU (West African Economic and Monetary Union) community. The wheelbases of these new axle configurations differ from one vehicle to another. This article evaluates the impact of axle wheelbases on longitudinal and transverse deformations at the bottom of the road surface and the base layer of a roadway. To achieve this, models of the pavement structure and different axle configurations were made using ALIZE LCPC 2.3.1 software. The results obtained at the end of the numerical simulation show that the maximum deformations under stress of the wide and isolated wheels are greater than those of the twin wheels. Longitudinal deformations in contraction and extension at the bottom of the asphalt concrete (BB) road surface and the gravel bitumen (GB) base layer vary slightly depending on the wheelbases of the dual or insulated wheel axles. This variation is due to the superposition of the contraction and extension deformations of the successive wheels. As for transverse deformations, they are strongly influenced by axle wheelbases. These transverse deformations, at the bottom of the road surface, decrease during contraction and increase during extension when the axle wheelbase increases. But at the bottom of the base layer, they increase during the contraction cycle and remain almost invariable in an extension phase with the evolution of wheelbases. During the study, it was also found that the addition of axles impacts the peaks of the different deformations.

Wheelbases, transverse deformations, longitudinal deformations, contraction, extension