What data is required to elaborate a diagnosis?
To make a successful diagnosis of a bridge, it is essential to be provided with the appropriate data to carry out the assessment.
To accomplish this, the prior inspection, outlined in the previous chapter, will be essential, in which a series of data on the bridge and its components must have been obtained, which, at this point, must be analysed. Therefore, all the information collected by the inspectors during the work in the field must be processed to calculate/estimate a series of indicators that will allow optimal
management of the bridge.
In this regard, first, a comprehensive and descriptive list of the damages detected in each of the elements should be generated. Those damages should be organised preferably in the following groups:
At this stage, having generated the catalogue of damages, classified in the groups described above, if doubts exist about the extent, consequences, cause, etc., of any defects found, a special inspection should be conducted to clarify all these issues.
Within each of the groups, each of the observed damages must be detailed, including, for each of them, the damage category. The damage category measures the relevance of the possible consequences of its greatest intensity to the bridge’s functionality and safety.
A damage’s category is determined by its nature and by the elements it affects, including what these elements are made of. This data will be taken by the inspector in the field, where for each damage identified he will evaluate its progress on a scale from A to D, with A being the least progress and D the most progress.
It is impossible to list here all the damage categories associated with each type of deterioration of the different elements.
But to give an idea of the concept, the following examples are given: buckling or collapse of the abutments would qualify as category D, while the appearance of dampness or surface vegetation on the abutments would constitute category B, whereas if the vegetation is rooted, it could reach category C.
Some defects, at their highest level of intensity, cause a maximum level of severity. However, there are other defects that, even at their highest intensity, cause only intermediate levels of severity.
Both types of defects, as their intensity increases, can lead to other forms of damage. In addition to the damage category, for each of the observed damages, the intensity of the observed defects must be indicated. This parameter refers to the degree of progress or extent of deterioration at the time of the inspection.
This data will be gathered by the inspector on site, where for each damage identified, the evaluation of its progress should be done on a numeric scale (1 to 4).
