A review of common NDTs in the monitoring and preservation of historical architectural surfaces

ABSTRACT

This contribution deals with the application of non destructive techniques (NDTs) in the assessment and monitoring of the state of conservation of historical architectural surfaces, during and after restoration and maintenance interventions. The aim is to present the authors’ direct and in-situ experience with the applications of NDTs among noteworthy real case studies in relation to selected common types of decay. Thermal imaging, ultrasonic investigation, testing for the assessment of physicochemical properties, and Raman spectroscopy were all performed in order to address, diagnose, and monitor: detachments, loss of material coherence, discoloration, superficial deposits, and rising damp and moisture in several important Italian built heritage (e.g., the Ghirlandina Tower in Modena, the Sacra of San Michele near Turin, and the Narthex of Saint Mark’s Basilica in Venice).

KEYWORDS:

• Architectural surfaces
• intervention monitoring
• IR thermography
• portable Raman spectroscopy
• ultrasonic measurements

Acknowledgments

The authors thank Prof. Claudia Daffara from the University of Verona (previously CNR-INO, Florence) and Dr. Marta Melchiorre di Crescenzo (previously at Ca’ Foscari University of Venice) for the IR-thermography, and Prof. Piercarlo Romagnoni and Dr. Massimiliano De Bei of IUAV for their technical support and the use of IR equipment. The authors would like to acknowledge, the students of the Master Degree students in “Chemical Sciences for the Conservation and Restoration” at Ca’ Foscari University of Venice A.Y. 2014–2015; The Proto of Saint Mark’s Basilica arch. Ettore Vio. The authors want to thank Jade Straker for her linguistic support.

Funding

This research was possible thanks to the financial support from Ca’ Foscari University of Venice (IRIDE departmental fund) and the EU JPI project EMERISDA.

Additional information

Funding

This research was possible thanks to the financial support from Ca’ Foscari University of Venice (IRIDE departmental fund) and the EU JPI project EMERISDA.