What post-repair actions should be carried out to ensure its effective implementation?
A repair intervention involves elements of a preexisting structure interacting with new ones, which makes it difficult to predict how the structure will perform. Therefore, after the execution of a repair, a very thorough control of the repair should be carried out to confirm that the intervention carried out is working properly and as intended.
In this regard, it is important to differentiate between two baseline scenarios when undertaking a repair, which will make the subsequent follow-up of the repair diverge completely.
There is an ideal first case, which must always attempt to be achieved, in which prior to the repair all the relevant investigations and a complete study of the structure to be repaired (not only of the damage to be repaired) have been conducted.
In this situation, after the execution of the works, it is essential (as in any executed project) to carry out the appropriate execution controls, with particular emphasis on specific aspects of repairing, such as the interaction of the existing structure with the new elements executed.
After this, it will not be necessary to undertake any special control of the repaired, areas, other than those normally conducted on bridges (inspections or instrumentation and monitoring systems, if any).
However, unfortunately, in many European regions, the situation is that the funding for bridge repairs is severely limited and only allows for very limited studies restricted to the areas where deterioration has been observed. As a result, localised repairs end up being undertaken without a full study of the structure, which does not really allow the true integration of the entire bridge with the repair to be known. In addition, there is a risk of having hidden defects, which then lead to the failure of the repair.
This situation should definitely be avoided but ACRP is aware that it is a reality in many countries, so below we provide a few guidelines for post-repair measures to be implemented in these cases.
A period of observation should be established to assess the structural integrity and efficiency of the repairs or actions, especially in the early phases, when there is a greater degree of uncertainty about the structure’s performance and response.
Moreover, it is important to identify the most sensitive and/or vulnerable points in advance, by analysing the potential risks that may occur before and after the repair.
