Behavior of the Leaning Tower of Pisa: Analysis of Experimental Data from Structural Dynamic Monitoring


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Understanding the structural behavior of heritage buildings is usually a very complicated task because they typically present complex deterioration and damage patterns which cannot be fully evaluated by means of visual inspections. Moreover, the reliability of such constructions largely depends on different materials, structural components and details, the health of which is often unknown or affected by great uncertainties. In this regard, the experimental dynamic testing of heritage buildings and monuments subjected to ambient vibrations has become a valuable tool for their assessment because of the minimum interference with the structure. Traffic-induced vibrations are not always a feasible dynamic load for monumental buildings due to their very low intensity or owing to existing restrictions to road and rail traffic. On the other hand, the analysis of the experimental response under earthquakes can lead to more relevant information about the dynamic behavior of historic constructions, provided that the structure is equipped with a permanent sensor network. Within this framework, the present work illustrates preliminary results carried out from time and frequency domain analyses performed on the experimental dynamic response of the leaning tower of Pisa using seismic records. The main dynamic features of the monument have been identified, and then examined taking into account the seismic input and the soil-foundation-structure interaction.



Edited by:

Giorgio Monti and Enzo Martinelli




R. Bartelletti et al., "Behavior of the Leaning Tower of Pisa: Analysis of Experimental Data from Structural Dynamic Monitoring", Applied Mechanics and Materials, Vol. 847, pp. 445-453, 2016

Online since:

July 2016




* - Corresponding Author

[1] G. Russo, O. Bergamo, L. Damiani, D. Lugato, Experimental analysis of the Saint Andrea" Masonry Bell Tower in Venice. A new method for the determination of "Tower Global Young's Modulus E, Engineering Structures, Vol. 32, No. 2, February 2010, pp.353-360.


[2] G. Bartoli, M. Betti, S. Giordano, In situ static and dynamic investigations on the Torre Grossa masonry tower", Engineering Structures, Vol. 52, July 2013, pp.718-733.


[3] A. Saisi, C. Gentile, Post-earthquake diagnostic investigation of a historic masonry tower, Journal of Cultural Heritage, in press.


[4] N. Nisticò, S. Gambarelli, A. Fascetti, G. Quaranta, Experimental dynamic testing and numerical modeling of historical belfry, International Journal of Architectural Heritage, in press.


[5] G. Quaranta, G. C. Marano, F. Trentadue, G. Monti, Numerical study on the optimal sensor placement for historic swing bridge dynamic monitoring, Structure and Infrastructure Engineering, Vol. 10, No. 1, 2014, pp.57-68.


[6] G. Monti, F. Fumagalli, G. C. Marano, G. Quaranta, R. Rea, B. Nazzaro, Effects of ambient vibrations on heritage buildings: overview and wireless dynamic monitoring application, Proceedings of the 3rd International Workshop Dynamic Interaction of Soil and Structures - Dynamic Interaction between Soil, Monuments and Built Environment, Rome (Italy), December (2013).

[7] R. Bartelletti, G. Fiorentino, G. Lanzo, D. Lavorato, G. C. Marano, G. Monti, C. Nuti, G. Quaranta, F. Sabetta, Behavior of the leaning tower of Pisa: insights on seismic input and soil-structure interaction, Proceedings of the 2nd International Symposium Advances in Civil and Infrastructure Engineering, Vietri sul Mare (Italy), June (2015).


[8] Y. Nakamura, E. D. Gurler, J. Saita, Dynamic characteristics of leaning tower of Pisa using microtremor - Preliminary results, Proceedings of the 25th JSCE Earthquake Engineering Symposium, Tokyo (Japan), Vol. 2, 1999, p.921–924.

[9] G. Macchi, S. Ghelfi, Problemi di consolidamento strutturale, vol. 3, No. 2, (2002).

[10] S. Castellaro, F. Mulargia, How far from a building does the ground-motion free-field start? The cases of three famous towers and a modern building, Bulletin of the Seismological Society of America, Vol. 100, No. 5A, October 2010, p.2080-(2094).


[11] C. Atzeni, A. Bicci, D. Dei, M. Fratini, M. Pieraccini, Remote survey of the leaning tower of Pisa by interferometric sensing, IEEE Geoscience and Remote Sensing Letters, Vol. 7, No. 1, January 2010, pp.185-189.