Damage evaluation in constructions based on geomatic and dynamic approaches

Résumé

It seems inevitable to confirm the steady improvement of materials and construction techniques in the field of civil engineering. The evolution from stones and bricks in masonry walls to selfcompacting concretes reinforced with steel fibers or pultruded polymers is enormous. However, it is important to remember that, similar to any living being, these construction methods are not impervious to pathological processes. Though their relevance and importance differ greatly depending on the material and the kind of pathological process, they should not be overlooked, since they will influence directly the construction’s life span. Driven by the latter, this Doctoral Thesis focuses on the development of methodologies and solutions that detect, evaluate, materialize and even foresee the pathological conditions which downgrade the bearing capacity of constructions. It endorses as well, global detection and damage assessment methodologies based on geomatics (through the use of laser-scanner and photogrammetric systems) and structure-dynamics (through the Operational Modal Analysis). In order to corroborate the applicability of the developed procedures, these have been applied in various construction types: ranging from historical buildings, vernacular architecture or buildings in an experimental phase, to “modern” constructions erected with reinforced concrete. The obtained results lead to the conclusion that the sensors that have been used, as well as the techniques and methodologies that were developed, have earned an essential role in the structural evaluation of constructions. Laser-scanner and photogrammetric systems are capable of providing “plentiful” products in terms of geometric and radiometric qualities. Nevertheless, they require complementary methods in order to mechanically materialize possible building damage (except for the results provided by strategies based on Digital Image Correlation). This need is met using structure dynamic-based techniques, specifically the Operational Modal Analysis, and the Finite Element Method. Said disciplines offer a wide range of possibilities for quantifying and detecting structural pathologies in constructions.