2016 - Slovakia - Road Roughness Limit Values Based on Measured Vehicle Vibration

This study identified longitudinal road roughness limit values based on measured vibration induced in a road-vehicle-driver interaction system. Therelations between measuredvehiclevibrationresponseand theinternationalroughnessindex(IRI) were summarized. Frequency-weighted acceleration on the seat and dynamic load coefficient (DLC) were used to quantify ride comfort, ride safety, and the dynamic load of the vehicle and road. Linear relationship coefficients were identified or taken from references. The expected large range of vibration responseroot mean square (RMS) values wasobserved for the same levelof IRI. IRI limit values were derivedfor chosen threshold values of vehicle vibration response as a function of vehicle velocity. Velocity-related IRI limit curves were proposed based on the fitting of IRI limit values lower envelope. IRI limit curves were compared with threshold proposals of other authors and width thresholds used in road maintenance. Some of the estimated IRI limit curves for DLC response were below thresholds used for road maintenance.