Radar detection of pedestrian-induced vibrations on Michelangelo's David

• Published in: PloS one Vol. 12; no. 4; p. e0174480
• Main Authors: Pieraccini, Massimiliano, Betti, Michele, Forcellini, Davide, Dei, Devis, Papi, Federico, Bartoli, Gianni, Facchini, Luca, Corazzi, Riccardo, Kovacevic, Vladimir Cerisano
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 10.04.2017; Public Library of Science (PLoS)
• Subjects: Accelerometers; Accelerometry; Biology and Life Sciences; Engineering and Technology; Engineering research; Environment; Environmental monitoring; Historical structures; Humans; Interferometry; Italy; Loads (forces); Mathematical models; Measuring instruments; Mechanical properties; Medicine and Health Sciences; Memorials & monuments; Models, Theoretical; Monitoring systems; Museums; Numerical models; Pedestrians; Physical Sciences; Radar; Radar detection; Resonant frequencies; Sculpture; Tourists; Traffic; Transportation; Vibration; Vibrations; Walking; Italy; San Marino
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0174480

This paper summarizes the results of a two-day dynamic monitoring of Michelangelo's David subject to environmental loads (city traffic and pedestrian loading induced by tourists visiting the Accademia Gallery). The monitoring was carried out by a no-contact technique using an interferometric radar, whose effectiveness in measuring the resonant frequencies of structures and historic monuments has proved over the last years through numerous monitoring activities. Owing to the dynamic behavior of the measurement system (radar and tripod), an accelerometer has been installed on the radar head to filter out the movement component of the measuring instrument from the measurement of the David's displacement. Measurements were carried out in the presence and absence of visitors, to assess their influence on the dynamic behavior of the statue. A numerical model of the statue was employed to evaluate the experimental results.