Dynamic identification and monitoring of cultural heritage buildings

Abstract

Preservation of architectural heritage is considered a fundamental issue in the cultural life of modern societies. This heritage is accumulating damage due to deterioration of materials, repeated loading and exceptional events. This means that conservation, repair and strengthening are often necessary. In this process, monitoring and non-destructive testing play a major role, providing information on the building condition and existing damage, and allowing to define adequate remedial measures. Dynamic based methods are an attractive tool because they are non-destructive and are able to capture the global structural behavior. The present paper focuses on three main aspects related to dynamic identification and monitoring: (a) exploring damage in masonry structures at an early stage by vibration measurements, using one arch model constructed in the laboratory. Progressive damage was induced in the arch and sequential modal identification analysis was performed at each damage stage, aiming at finding adequate correspondence between dynamic behavior and internal crack growth. The dynamic based methods allowed detecting and locating the damage; (b) two complex case studies of modal and structural identification of monuments using conventional sensors. Operational modal analysis was used to estimate the modal parameters, followed by statistical analysis to evaluate the environmental effects on the dynamic response. The aim is to explore damage assessment in masonry structures at an early stage by vibration signatures, as a part of a health monitoring process; (c) finally, a comparison between commercial wireless based platforms and conventional wired based systems is presented for a laboratory specimen and a structural element from a 15th century building.