Verification of the roughness guideline for Dutch state highways : contribution to the First International Symposium on Surface Characteristics

On account of the considerable length of state highways to be maintained and the financial means needed therefore, a verification on a limited scale of the actual maintenance guideline for the roughness (riding comfort) was considered to be sensible. In order to have disposal of the necessary data, the Road and Hydralic Engineering Division (DWW) took part in an experiment with a rating panel on the test track facility of heavy-vehicle manufacturer DAF Trucks BV. Furthermore the DWW carried out extensive measurements on the same facility with the APL-profilometer (APL = Analyseur de Profil en Long). In addition to this the APL-profilometer was examined by the Delft University of Technology. Results of subjective panel ratings and objective measurements were statistically analysed by the Institute of Applied Informatics (ITI- TNO). A relation between the panel ratings and APL measurements was established and consequently the maintenance guideline for the roughness (riding comfort) of state highways was verified. The paper also pays some attention to road safety, as an aspect connected with the rideability of road surfaces.