Technologies and tools for the diagnosis and conservation of Cultural Heritage.Diagnosis, products and procedures for the conservation of built heritage

The conservation of built heritage requires detailed knowledge of the characteristics of its constituent materials and their state of conservation, making it possible to identify risk factors and conditions as well as the need for specific measures. On the basis of this knowledge the most effective intervention strategies and the most suitable conservation solutions can be selected.
Over the years, IBAM, in its own diagnostic and conservation laboratories, has studied the causes and mechanisms of decay affecting a range of stone materials used in historic buildings in comparable contexts across the Mediterranean basin, together with the measures adopted for their conservation.
The diagnostic activities have involved numerous case studies relating to items of historical, architectural and archaeological heritage (Teatro Petruzzelli and Cathedral in Bari; Santa Croce Basilica in Lecce; Cathedral in Altamura, etc.). Integrated methods both in situ (sonic and ultrasonic techniques, X-Ray fluorescence, penetrometric and rebound tests) and in the laboratory (optical and electronic microscopy, X-Ray diffractometry, ion chromatography, Fourier transform infrared spectroscopy and microscopy, thermogravimetry, mercury porosimetry) have been used in order to optimise the diagnostic data, searching for correlations between in situ and laboratory results, and to determine the most effective diagnostic
procedures. Particular attention has been paid to the use of non-destructive in situ tests and minimally destructive laboratory analyses such as those based on Environmental Scanning Electron Microscopy technology. At the same time the durability of stone materials has been studied with a view to identifying the parameters of correlation between their intrinsic characteristics and their on-site behaviour. This has entailed the mineralogical, petrophysical, geochemical and mechanical characterisation of quarry materials, with particular reference to the search for correlations between the nature of their mineralogical constituents, their porosimetric characteristics, water absorption mechanisms, transfer of mechanical stress and artificial ageing processes based on saline crystallisation cycles.
Regarding the study of conservation measures, over the years IBAM has conducted experiments to assess treatments for the conservation of stone materials used in historical, architectural and archaeological buildings. The aim is to evaluate the performance of products for conservation and restoration and to fine-tune intervention procedures with regard to both the products and the substrates to which they are applied. Particular attention has been paid to conservation issues affecting soft and highly porous stones and to verification of the application potential of innovative experimental products such as nano-structured materials (photocatalytic titania, nanosilica, etc), products with low environmental impact (such
as water-based dispersions) and nanotitania-based restoration mortars. In addition, studies have been conducted to assess the results of conservation treatments under real conditions, by means of in situ monitoring of measures implemented in the past on selected Lecce Baroque artefacts.
The diagnostic and conservation activities described above are strongly multidisciplinary in nature. Over the years, they have been conducted in the context of externally funded research projects, based on cooperation and partnership with other research institutes and the private sector (especially SMEs). These activities are currently being conducted in the form of services and expertise provided to conservation authorities (Superintendencies), local government, companies and restoration planners.