Title: Four years of structural health monitoring of the San Pietro bell tower in Perugia, Italy: two years before the earthquake versus two years after

Authors: Pier Francesco Giordano; Filippo Ubertini; Nicola Cavalagli; Alban Kita; Maria Giovanna Masciotta

Addresses: Department of Architecture, Built Environment and Construction Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy ' Department of Civil and Environmental Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia, Italy ' Department of Civil and Environmental Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia, Italy ' Department of Civil and Environmental Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia, Italy ' Department of Civil Engineering, Campus de Azurém, University of Minho, 4800-058 Guimarães, Portugal

Abstract: This paper addresses the structural health monitoring (SHM) of the bell tower of the Basilica of San Pietro in Perugia, Italy, which is located in a seismic area. Known as one of the landmarks of the Umbrian capital, the tower belongs to a monumental complex of exceptional historical and cultural value. Therefore, its protection with respect to earthquakes is an important issue. To this purpose, a vibration-based SHM system able to detect anomalies in the structural behaviour by means of statistical process control tools has been installed in the tower and is under continuous operation since December 2014. The effects of the 2016-2017 Central Italy seismic sequence were clearly detected by this system, even if earthquakes took place at relatively large distance from the bell tower. The large amount of SHM data collected over four years allowed to assess the modifications in the structural behaviour of the bell tower in post-earthquake conditions.

Keywords: structural health monitoring; SHM; operational modal analysis; OMA; post-earthquake assessment; environmental effects; heritage structures; masonry towers; preservation of architectural heritage; Italy.

DOI: 10.1504/IJMRI.2020.111797

International Journal of Masonry Research and Innovation, 2020 Vol.5 No.4, pp.445 - 467

Received: 20 Dec 2018
Accepted: 10 May 2019
Published online: 15 Dec 2020 *