Long-term structural monitoring of the damaged Basilica S. Maria di Collemaggio through a low-cost wireless sensor network

Abstract

The work presents the inter-disciplinary multi-year project focused on the permanent seismic monitoring of a historical structure, the Basilica S. Maria di Collemaggio, by means of an advanced wireless sensor network. Considered among the architectural masterpieces of the Italian Romanesque, the structural behaviour of the monumental masonry church is strongly debated after the heavy damages and the partial collapse that occurred during the 2009 L’Aquila earthquake. From the perspective of information technology, critical issues in the wireless data acquisition and communication are analysed. The sensor network design, deployment and performance are discussed with respect to the high-demanding service requirements—as well as the non-negligible management costs—specifically related to the long-term monitoring of a monumental masonry structure in a seismic area. From the perspective of experimental signal analysis, the acceleration data collected during a 3-year period of seismic monitoring are analysed in the frequency and time domains. The results allow the clear detection of complex interactions between the masonry structures and some of the temporary protective installations. Stochastic subspace identification procedures are applied, with critical analysis of their effectiveness in the assessment of reliable modal models from the building response to real seismic events. Finally, the robustness of the modal identification obtained from the structural responses to different near- and far-field micro-earthquakes is discussed, with the aid of numerical models of the damaged and protected church configuration

Ambient Vibrational Characterization of the Nossa Senhora Das Dores Church

“…Essentially, the identification of the structural dynamic properties are an useful tool for safety analysis, making possible the investigation of damages influence on global behavior of structures, as previously demonstrated (Potenza et al 2015). Moreover, this tool can also provide useful information for be used in support of structural risk reduction, as for instance for be used in accordance with proceedings described in (dei Ministri 2011) and (CIB 2010).…”

“…Ambient vibration measurements were obtained and analyzed by (Potenza et al 2015) for to characterize and monitoring the Basilica di Santa Maria Col-lemaggio, in Italy. The partial collapse of the church after L' Aquila earthquake in 2009, make increase the uncertainties on its structural behavior, motivating the necessity of characterization and monitoring of this historical construction from Italian Romanesque period.…”

Reliability of Mems Accelerometers for Instrumental Intensity Mapping of Earthquakes

“…Sensor belongs to a family of products suitable for a variety of applications including mobile terminals, gaming and virtual reality input devices, antitheft systems and inertial navigation, appliance and robotics [ST Microelectronics 2008. The same sensors are known to be widely used for the structural health monitoring [Gattulli 2013, Potenza et al 2015Rice et al 2010] and for earthquake early warning networks [Peng et al 2013].…”

Modal identification of localised damage in beams and trusses: experimental and numerical results

“…A first step in this direction is the definition of an accurate numerical model of the structure in its actual conditions, including the identification of possible damages. To this respect, the identification of modal properties, as natural frequencies, modal damping coefficients and mode shapes in a linear elastic structure can be used to verify the correspondence of a Finite Element (FE) model of the structure to its real behaviour, updating the numerical model on the base of experimental tests (D'Ambrisi et al 2012;Diaferio et al 2015Diaferio et al , 2018Gentile and Saisi 2010;Potenza et al 2015;Ivorra et al 2016;Antonacci et al 2012;Sepe et al 2005aSepe et al , b, 2017Valente et al 2016;Bedon et al 2016). Moreover, the experimental modal analysis techniques are able to highlight some peculiarities of the structural response that are usually neglected or that are difficult to be evaluated in the design process (as the influence of the non-structural elements on the dynamical response of the building, the presence of inhomogeneities, etc.…”