Proposal of Road Unevenness Classification Based on Road Elevation Spectrum Parameters

摘要

Road classification of longitudinal road unevenness was proposed based on road elevation power spectral density (PSD). The proposal is based on two spectrum parameters (unevenness index and waviness): vehicle model vibration response, and vehicle velocity. A planar model of a personal car with 12 degrees-of-freedom (DOF) was used and four vertical vibration responses were considered. Ride comfort quantities in terms of the frequency-weighted acceleration on driver and passenger seats and ride safety/pavement dynamic load quantities as a dynamic load coefficient (DLC) on the front and rear axle were taken into account. A tire-enveloping model was used as representative of tire-road contact. This approach was compared with pure tire-road point contact and moving averaged profile. Data was obtained for 1600 real road sections and three different velocities. The results indicated marked differences in comparison with the road classification based on a constant waviness according to the ISO 8608 standard.