This study uses the periodic surveys of the degradation of Guinea’s paved roads from the country’s Road Database. Processing
the data from five representative sections shows that these structures suffer recurrent degradation, often located at the same places
on the roads. These degradations are mainly manifested by deformations of the pavement, marked by collapses and pronounced
ruts. Simulations with the Alize software show that the causes of these disorders are mainly related to problems of the evolutionary
bearing capacity of the lateritic support soil between dry and wet periods. This parameter is apparently not yet well integrated into
current methods of pavement design in tropical climates. This work can therefore be used to initiate new studies of the mechanical
and dimensional behaviour of lateritic materials according to climatic cycles and of the improvements that can be made to them by
treatments with hydraulic binders in particular.