Steel bridge over El Barranc d'Aigües (analysis)

A detailed assessment of the condition of an object.


Element type
The section chosen to be monitored was the isostatic span of 21.12 meters length. This span was chosen because of a fatigue study performed to the previous old bridge, which was then replaced for the current bridge in 2018 with same overall structural scheme. This case study presents a simple and fully automatable vibration-based Structural Health Monitoring (SHM) alert system. The proposed method consists in applying an Automated Frequency Domain Decomposition (AFDD) algorithm to obtain the eigenfrequencies and mode shapes in real time from acceleration measurements, allowing to provide a diagnosis based on a Support Vector Machine algorithm trained with a database of the modal properties in undamaged and damaged scenarios accounting for temperature variability. The result is an alert system for controlling the correct performance of the structure in real time with a simple but efficient approach. Once the alert is triggered, the undamaged mode shapes (which could be previously stored in a database of modal parameters classified by temperature) and the current (damaged) mode shapes, can provide guidance for further application of Finite Element Model Updating (FEMU) techniques.
Case type
Initiation of assessment
Pure research interest
Predominant verification type
Predominant verification scale
Structural system
Structural analysis
Modal analysis
"Modal analysis" is not in the list (Ultimate limit state, Fatigue limit state, Serviceability limit state, Proxy limit state, Other) of allowed values for the "Structural analysis" property.
Information updating
Indirect non-bayesian
Operational intervention