MEASUREMENT OF ROAD ROUGHNESS

Abstract

Roughness is deviation of a surface from a true planer surface. No surface is perfectly smooth, even though it appears so to the naked eye and the road is no exception. Measurement of road roughness can be of interest for both civil and vehicle dynamics engineers. This dissertation work involves measurement of road roughness. Surface profile is obtained using a trailer unit and the power spectral density is obtained. Signals are obtained from velocity and acceleration transducers fitted on the trailer unit. These signals are digitized using an ADC card. Digital signals are filtered and processed according to requirement to obtain the surface profile. Low pass and band pass filters are used. These filters are finite impulse response (FIR) type filters. The surface profile is plotted on screen. This is a on-line process. Power spectral density of road profile is obtained and compared with standard results given by International Standards Organization. Based on the comparison of the results, test roads are classified