Numerical insights on the seismic risk of confined masonry towers

• Published in: Engineering structures 2019-02, Vol.180, p.713-727
• Main Authors: Bartoli, Gianni, Betti, Michele, Galano, Luciano, Zini, Giacomo
• Format: Article
• Language: English
• Subjects: Confined masonry towers; Cracking pattern; Cultural heritage; Cultural resources; Damage patterns; Earthquake damage; Environmental risk; Finite Element modelling; Guidelines; Historical buildings; Historical structures; Italian Guidelines; Masonry; Mathematical models; Mechanical properties; Mitigation; Nonlinear static analyses; Risk assessment; Seismic activity; Seismic engineering; Seismic hazard; Seismic response; Seismic risk assessment
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2018.10.001

•Numerical study on the seismic behaviour of masonry towers.•Critical insight into the results obtained.•Comparison between seismic risk of confined and unconfined structure. This study analyses the seismic risk of a confined historic masonry tower located in Italy (San Gimignano) critically discussing the multilevel assessment path proposed by the Italian “Guidelines for the assessment and mitigation of the seismic risk of the cultural heritage”. Specifically, these guidelines identify a methodological path which aims to coordinate the phases of investigation and drive the grade of resolution of the structural assessment, depending on different possible objectives. The paper compares the results obtained with the three different levels of evaluation employed to estimate the seismic risk of the tower: level LV1 (analysis at territorial scale), level LV2 (local analysis) and level LV3 (global analysis). The main variables considered are the mechanical properties of the masonry walls and the degree of constraint generated by the buildings surrounding the tower with specific attention to the latter variable. Numerical insights on the seismic behaviour of the tower are presented and discussed through a comparative approach. The obtained results show significant differences between the numerical models of the confined and the isolated tower in terms of both capacity curves and damage pattern and point out the needs of additional studies regarding the numerical assessment of the effects of the interaction between a tower and its adjacent lower buildings.