What is structural monitoring and what are its main objectives?
A bridge should be tracked during its service life to detect, address, or minimise any damages that may arise and that can affect its performance. The structure’s follow-up can be accomplished in two ways:
1. Inspections
Assessment procedure in which a qualified specialist inspector observes, classifies, and documents the deterioration(s) of a structure. In addition to visual inspections, tests are usually conducted.
Typically, it is one of the first steps in assessing the condition of concrete structures. This is what has traditionally been done to ensure the correct operation of structures. With inspections, the structure is punctually followed up.
2. Structural monitoring
The purpose of this method is to observe the behaviour of a structure continuously over time employing instrumentation. Monitoring structural behaviour allows for the early detection of anomalies, which allows for more efficient maintenance and repair measures, resulting in lower operating costs. Monitoring replaces, complements, or improves some periodic maintenance tasks with maintenance that is tailored to the conditions of a structure at a given time.
This offers interesting advantages, such as knowledge of the real behaviour of the structure and the reduction of uncertainties, continuous observation, automation of maintenance, early detection of damage, possible extension of service intervals or cost and time savings.
The structural monitoring of a bridge consists of observations and analyses over time to identify the variation of any of the characteristics that may lead to a degradation of its present or future performance.
Periodic, online, and automatic inspection differentiates this technique from traditional punctual inspections. For this, instrumentation is used, which consists of equipping a structure with various types of sensors that can measure various magnitudes, including acceleration, speed, displacement, unit deformations, etc., in addition to establishing durability parameters.
The fundamental objective of a structural monitoring program is to answer the following questions:
The last issue involves the diagnosis of the condition of the bridge or one of its elements to estimate, by predicting future deterioration, the remaining service life.
The combined use of structural surveillance/monitoring and diagnosis of a structure makes it possible to make informed decisions about the use, operation, maintenance, and decommissioning of a bridge and thus enables active management of its life cycle.
