Predicting Pavement Deterioration Modes Using Waveband Analysis

Road roughness is the result of a chain of distress mechanisms, and it combines the effects of various modes of pavement deterioration. The common measure of roughness is the international roughness index (IRI). The IRI represents the functional performance of road pavements and serves as an indicator of the structural performance. However, the use of the IRI in setting priorities for maintenance and rehabilitation programs has some flaws. The IRI cannot detect the mode and rate of pavement deterioration that contribute to the surface roughness. In addition, the IRI may be a poor measure of truck ride and the dynamic wheel loads generated by the interaction of heavy vehicles and rough road surfaces. Roughness spectrum can be divided into certain wavebands, with each waveband corresponding to a certain mode of pavement deterioration. The power spectral density analysis of road profiles is used to view the distribution of the various wavelengths within the profile and to show the contribution of each waveband to roughness. Waveband analysis can help overcome the shortcomings of the IRI, and it provides information that helps road authorities in planning rehabilitation programs and managing the road network.