Nondestructive Evaluation of Plasters on Historical Thin Vaults by Scanning Laser Doppler Vibrometers

Abstract

Non destructive evaluation of plasters on historical thin vaults by scanning laser Doppler vibrometers was attempted in this article. The aim was to investigate the state of conservation of historical plasters hanged from thin light vaults made by plaster and reeds that often carried on their lower surface frescoes and stuccos of high historical, artistic and architectural value. SLDV could represent an effective support for the diagnostic process of these construction system. In particular, the first results underline that processing the data so asto estimate the so-called Operational Deflection Shapes (ODS)does not seem to be helpful as a damage indicator, on the contrary modal analysis seems to be effective in localizing damages present in the specimen. KEYWORDS: thin vaults; SLDV; historical plaster; NTD; diagnostic of cultural heritage; plaster and reeds vaults.

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