ROAD UNEVENNESS - PAPER PRESENTED AT THE 1998 FISITA WORLD AUTOMOBILE CONGRESS, PARIS

Surface characteristics of pavements have a significant influence on the comfort and safety for the road users. Fuel consumption and vehicle wear are expenses the road users meet every day and in order to keep these to a limit and to assure comfortable and safe roads it is necessary to be able to measure pavement surface characteristics. One of the characteristics which plays an important role in this connection is the pavement's longitudinal and transverse evenness. Bumpy roads produce poor riding comfort and increase driver fatigue. Poor transverse evenness equals rutting and increases the risk for aquaplaning and often results in situations that the driver cannot control. Today many sophisticated measuring systems are used around the world to measure the evenness of pavements. Modern technology makes it possible to measure the longitudinal and transverse profiles very precisely even if the measuring equipment is placed in a vehicle operated at normal traffic speed. Even with the introduction of modern technology and modern data handling techniques, it is seen that these profiling equipments vary widely from country to country. PIARC is therefore conducting an experiment to compare and evaluate results measured by using different equipment and varying measurement methods. The experiment is anticipated to take place in USA, Japan and Europe in 1998 conducted as three separate regional experiments to facilitate for differences in practice in the regions. PIARC's role in the experiment is to act as an umbrella organisation assuring a common benefit by linking the experiments together by means of a core program. As the experiment will be conducted in 1998, the paper will not be able to report the complete result of the outcome from all three regions. The paper will however, present the status and first achievements of the experiment and present the work to be completed before the PIARC World Congress in 1999.