The map below displays, for all countries for which data is available, the main inspection intervals in months.
During the main inspection, the conservation status is surveyed based on a close inspection by hand, documented and evaluated. If needed, necessary measures are suggested. In consultation with the party responsible for maintenance, the documentation must also be in the form of meaningful visual material that can be clearly assigned to the inspected location on the object, e.g. on the basis of plan drawings. A competent engineer with relevant experience in the inspection of structures or structural planning is to be entrusted with the management of the inspection. This person must be able to assess the basic structural condition of the object to be inspected and estimate the influence of damage on the load-bearing capacity, serviceability and durability of the structure. Depending on the size of the objects to be inspected, he must have personnel and suitable equipment. If the specified scope of testing is not sufficient, special tests must be arranged. In the course of the assessment, the evaluation of the following components should be planned:
|Substructure||Foundation elements, abutments, piers, wing walls, channels, embankments|
|Surface course||pavement, sidewalk and cycle path pavement and their connections Bridge bearings|
|Expansion joints||Expansion joint structure including elastic pavement expansion joints|
|Waterproofing||drainage Bridge waterproofing and drainage facilities such as drains, drain pipes, fasteners|
|Border beams||Border beams including curbs and border beam joints|
|Other equipment||Railings, vehicle restraint systems, noise protection equipment, splash protection, drop guards, lighting, lines, general traffic signs, object-related traffic signs (e.g. clearance, weight restriction), etc.|
If a bridge has a measurement program (geotechnical, geodetic, crack widths, etc.) or monitoring system in place, the measurement results shall be made available for inspection and included in the evaluation. In terms of relevant documentation, the results of the last test and/or inspection as well as general plans showing the as-built condition shall be made available for the bridge inspection. If required, necessary technical documents and supplementary plans are to be consulted.
Maintenance strategy and limits
For the component assessment, condition grades are to be assigned for the individual components and, based on this, for the entire object. Assessment procedures can be assigned as before to the preventive maintenance strategy, in certain condition classes, a partially change to corrective maintenance strategies can also be identified, see (COST TU1406)WP1.
Structures such as bridges are usually inspected at intervals of about six years, or at shorter intervals if the condition of the object requires it. Some countries also allow an extension if there are no moving parts or with simple static conditions. The prerequisite for this is that the inspections are carried out properly and on time and that the serviceability of the object is confirmed to the previous extent.