Pavement Strengthening and Rehabilitation in Norway - Assessing the needs

Resumé

The Norwegian Pavement and Materials Design Guidelines were revised in 2005. A new system for road strengthening and pavement rehabilitation, based on an evaluation of the surfacing service life, was then introduced. In this new system the strengthening need is based on the Surfacing Life Factor (SLF). The SLF describes the relation between the functional (observed) surfacing service life and the expected surfacing
service life. Depending on this factor the need for strengthening is given:

SLF above 0,7 - the required strength improvement is considered to be taken care of by the ordinary resurfacings.
SLF 0.7 - 0.5 - the required strength improvement is expressed in term of structural number values and depends on the SLF and traffic volume.
SLF below 0.5 - indicates a pavement structure with serious deficiencies and a full investigation is required.
The change has been made possible by the introduction of the Norwegian pavement management system in 1990.