Development of deterioration models for local authority roads

This paper describes the use of an 11-year time series of condition measurements obtained from a random sample of road sections on all classes of one local authority's roads to evaluate the changing condition of the sections. The condition has been defined in terms of macro-texture, rut depth and longitudinal profile. Deterioration models have been developed using the repeat measurements after allowing for routine measurements. The results have also allowed initial estimates of required maintenance cycles to be established for macro-texture and for the development of rut depths. Longitudinal roughness values collected as part of the study suggest that the roads included in the study have overall structural capacity and that only the surface layers deteriorate.