SAMCO Final Report 2006 F09 Report on Bridge Management
4.9 Norway (NPRA)
Structures in the Norwegian road network owned by the Public Roads Administration are considered to be bridges when the accumulated spans or total length equals or exceed 2.5 m. Those are regularly inspected. The inspection types reflect the thor- oughness and frequency of inspections. The bridge inspection cycle starts when construction is complete at which point the acceptance and guarantee inspections are carried out. After the bridges have been handed over to the owner, routine in- spections shall be carried out for the rest of the bridge's service life. This involves the following inspection types:
which are described in the following.
General inspection: The purpose is checking for damage that can affect the load car- rying capability of structures’ traffic safety, and future maintenance or adversely af- fect the environment/aesthetics. Minimum requirements are that damage assessed as requiring repair by the next inspection shall be recorded, that is damage degree 3 or 4. The normal requirement is that general inspections are performed each year, and that the first inspection happens during the year after the hand over. General inspections may be dropped in the year of a major inspection.
For bridges with uncertain future development of damages it should be considered to inspect more frequently than generally recommended. The interval must be consid- ered and fitted for each bridge. Important factors to have in mind are: traffic volume, proportion of heavy traffic, bridge type and size, significance of the road network, low load carrying capability, condition and damage development that might lead to too low capacity, bridges exposed to flooding or erosion.
In special occasions it is possible to increase the intervals depending on total bridge length and bridge type. It is granted that the person responsible for the bridge man- agement, consider this when a major inspection is carried out. Maximum interval be- tween each general inspection is then:
2 years for bridges with span less than 10 m without streaming water under- neath,
1 year for bridges with span less than 10 m with streaming water underneath, for bridges with span equal or greater than 10 m and for movable bridges.
General inspections have to include a simple visual check. No measurements, mate- rials investigations or use of inspection equipment are required. Exposed details or locations should be checked in particular.
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