The requirement for harmonisation of methods for determining the skid resistance of road surfacings across Europe is explained. The intention is to establish equations to convert results provided by different measuring devices. Research conducted for PIARC has provided a large database which is a valuable tool for standardisation. An equation for calculating the `International Friction Index' is presented. Additional analysis led to the definition of a European Friction Index (EFI), the advantages of which are described. Trials were conducted with newer types of surfacing such as porous asphalt, porous cement concrete and thin surfacings. A draft standard was prepared which defines EFI and which proposes a procedure for calibrating friction devices based on EFI. The third draft of this standard is appended to this report.
Abstract