PSI - Issue 84

Rosario Montuori et al. / Procedia Structural Integrity 84 (2026) 967–974

969

3. The Methodology Following the completion of the Inspection Forms, the methodology for evaluating the condition of each individual structural element, and consequently of the entire bridge structure, is articulated through specific Damage Indices. In addition to the assessment of the defectiveness of structural elements, the intrinsic characteristics of the structure— namely structural age, structural scheme, sensitivity to deterioration, territorial importance, and potential indirect damage—are also analysed and translated into specific coefficients. It is important to emphasize that the resulting indices are significantly influenced by the quality of the inspections. More precisely, reference is made to the inspection reliability, which, in addition to depending on the level of care and thoroughness of the inspectors (assumed to be as high as possible), also depends on how many structural elements, or what portion of each individual structural element, can actually be inspected. Indeed, it must be taken into account that it is not always possible to inspect every single structural element, particularly when the bridges to be inspected cross obstacles such as railways, streams, or deep valleys. For this purpose, Reliability Indices have also been introduced for the obtained results, accounting both for the percentage of elements that can be inspected and for the inspectable portion of each individual element. Naturally, this parameter also represents a classification criterion, not so much with regard to maintenance needs, but rather with respect to the organization of more in-depth inspection campaigns.

Fig. 1. Flow Chart of the proposed methodology

Ultimately, the objective of the methodology is to perform a reasoned classification and a multilevel assessment of the bridges and viaducts managed by the Road Authority. This methodology is articulated through four phases: Phase 1 Inventory and census Phase 2 Inspection Phase 3 Risk assessment Phase 4 Classification