Integrated seismic early warning and structural health monitoring of critical civil infrastructures in seismically prone areas

Abstract

A large part of Europe is exposed to medium/high seismic risk. Throughout the past decades serious structural damage and collapse have occurred in different countries. Examples of structures at risk are existing infrastructure and public buildings. Efficient seismic protection is especially required in these structures. In fact, an earthquake can lead to a high number of injury or death since these structures are often crowded. On the other hand, strategic structures have to be fully operational to manage the aftershock emergencies. This article deals with some results of a research focused on the development of optimized structural health monitoring (SHM) technologies and data processing techniques for critical structures in seismically prone areas. Specific solutions are proposed to take advantage of seismic early warning systems (SEWSs), which are becoming very popular and effective worldwide. The most relevant aspects of seismic early warning (SEW) and SHM systems are herein reviewed and the main issues related to their integration are discussed in order to properly design the final system. Attention is mainly focused on dynamic behavior in operational conditions and on earthquake effects. Hardware and software solutions adopted for the characterization and monitoring of the dynamic response of a sample building are illustrated pointing out the capability of the same architecture to host data and information provided by SEW applications. Finally, datasets in operational conditions are used to evaluate the fundamental modal parameters of the structure by output-only techniques, whose potentialities and limitations in the presence of weakly and heavily nonstationary signals have been also assessed. In particular, they have been applied, respectively, to the records collected during crowded football matches hosted at the stadium located nearby the sample building and during the recent L’Aquila earthquake mainshock.