The International Roughness Index IRI is an essential input parameter for the evaluation of operational costs. In order to generate a predictive model of IRI a linking equation with the surface distress parameters is needed. Contributing to that purpose predictive models of slab cracking and joint faulting have already been developed by considering as a whole the actual behaviour of Chilean PCC pavements. In the paper a correlation is presented between the IRI and several indices of surface characteristics, mainly slab cracking, spalling and repairs determined through detailed visual surveying and absolute faultings measured at joints. The IRI is determined by continuous measurements made with an optical profilometer KJ-Law passing several times on 100-200 m long homogeneous sections of jointed concrete pavements selected to cover a range of surface distress. To use the profilometer a complete measurement methodology had to be developed to take into account a number of environmental effects that are controlling the performance of the Chilean in-service PCC pavements, such as the predominant upward concavity of slabs due to the yearly cyclic moisture warping and to the daily cyclic temperature curling.
Samenvatting