SAMCO Final Report 2006 F09 Report on Bridge Management
4.3 United Kingdom (TRL)
In the United Kingdom there are four main types of inspection for all bridges that meet the following requirements. A span greater than 3.0 m, culverts 1.8 to 3 meters span or multi-cell culverts with a cumulative span greater than or equal 5 m, if their cover to the road surface is less than 1.0 m. In Scotland the minimum culvert size is 2 meters. The four types of inspection in the United Kingdom are described in the following.
Superficial inspection: These are carried out regularly by staff from the Maintaining Agent. It is a cursory check of obvious defects that might lead to accidents or high maintenance costs. It can be made from ground and deck level or from any walkway or platform, built into a structure. If any superficial inspection reveals a possible de- fect, which is a hazard to road, rail or other users, the Maintaining Agent immediately takes the actions required to safeguard the public. The overseeing organisation and the owner of the structure are informed immediately.
General inspection: This is a visual examination of all parts of the structure, adjacent earthworks or waterways which can be visually inspected from ground and deck level or from any walkway or platform, built into a structure, without the need for special access or traffic management arrangements. Inspections are required not more than two years after the last General or Principal inspection.
Principal inspection: This is a close examination within touching distance of all in- spectable parts of the structure and adjacent earthworks and waterways, utilising suitable access or traffic management where necessary. The inspection is carried out at intervals set initially by agreement, which normally would be six years and excep- tionally may be up to ten years for less important structures. For the new structures it is carried out about one month before the end of the construction contract Mainte- nance Period, or opening of the structure to traffic. In recent years limited testing has been included.
Special inspection: This is a close examination of particular areas or defects causing concern. It is carried out to investigate a specific problem, either found during inspec- tion or already discovered on other similar structures. It is also carried out in other specific circumstances, for example on cast iron structures at intervals not exceeding six months, on structures strengthened using bonded plates and on structures which have weight or other forms of restrictions. Other examples include structures that have to carry an abnormal heavy load before, during and after the passage of the load, where a structural assessment has indicated that it is necessary.
Defects revealed during a superficial inspection are reported to the Maintaining Agent and appropriate action taken as described in the previous section.
The findings from General, Principal and Special Inspections are recorded on special forms. These include basic information such as structure number, structure name,
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