What should be the methodology for conducting these inspections?
In general, the bridge inspection is to be conducted in a detailed manner at a distance from each element that allows visual observation of signs of defects with the use of auxiliary means.
Depending on the type of inspection, a greater or lesser distance to the element to be inspected and more or less detail will be required to perform the observations. The following is a sample route of the structure, which should be modified according to the characteristics of the terrain, seeking the best observation of deterioration, and minimising the time required for the occupation of the track.
1. Visual inspection of the lower perimeter
This consists of the inspection of the surrounding terrain and the perimeter surfaces of the structure, emphasising the lower part of the structure. The watercourse will also be inspected, if present.
2. Visual zig-zag inspection from under the deck
The rest of the elements that can be inspected from the lower part of the structure shall be surveyed.
3. Visual inspection of the interior of beams and abutments
Whenever access is possible, defects inside beams and abutments shall be observed and noted in detail, to be compared with the observations already made from under the deck and with those to be made later from the top of the structure.
4. Visual inspection of the top face of the deck
Defects on the top face of the structure shall be observed and noted in detail.
All the information collected by the inspectors during their fieldwork shall be processed by computer systems to calculate a series of indicators for optimal asset management.
The indicators will differ according to the type of inspection to be performed, as the objective and scope of the different types of inspections are not the same.
The indicators for basic inspections neither can nor are intended to classify a bridge from a structural perspective, which is the role of the scheduled inspections, but to trigger an inspection by expert personnel to corroborate or dismiss the detected physical changes through the visual observation of a basic inspection. The following is a list (non-exhaustive) of the types of defects to look for in bridge inspections:
