This paper aims firstly to study two main toll motorways surface characteristics: the macrotexture and the coefficient of transverse friction, secondly to model their evolution according to the traffic increase. It provides an accurate description of the decrease of the surface characteristics along the traffic by using robust linear regression models. Besides their scientific interest, these findings provide the road managers with useful information to optimize the wearing courses maintenance works programming. Both individual and global evolution curves of texture, on the global road network, lead to the ability for newtwork manager to analyze and predict on long term the state of its road patrimony.
