2.8 Estimating the roughness of unpaved roads
Agencies responsible for road maintenance and planning must be able to assess road roughness. Road roughness affects vehicle safety, comfort and speed of travel, and thus the rate of wear of vehicle parts and, in turn, vehicle operating costs.
Instrumented measurement of roughness is desirable, but not feasible for unpaved roads. In these instances a subjective estimation is needed. This paper presents two possible approaches based on the World Bank's work with the Highway Design and Maintenance Standards Models (HDMIII, and HDM-4).
- The World Bank's 'Guidelines for conducting and calibrating road roughness measurements', provides a methodology using adjectives and some quantitative information to describe road surface conditions and ride sensations
- The 'limiting speeds' approach is based on field measurements in Brazil and Australia and, as it pertains to roughness, is the maximum speed a vehicle can attain given road roughness alone; it is independent of factors such as gradient and engine power:
Issuing body: World Bank
Type: Technical paper
Title: Unpaved roads' roughness estimation by subjective evaluation
File type: PDF
File size: 28.84 KB
Year of publication: 1999
Number of pages: 3
