Integrated non invasive tests for the architectural restoration of the Tricarico Cathedral

The Restoration of a monument is based on the diagnosis of decay pathologies and instability factors that affect it. This diagnosis could be pursued by means on different diagnostic methodologies among which the non invasive ones are desirable because of the brittleness of cultural heritage. In this paper we show an integrated diagnostic approach based on the use of Ground Penetrating Radar (GPR) and Sonic Prospecting applied to the Cathedral of Tricarico in the Basilicata region (Italy), affected by heavy instability phenomena and a widespread deterioration of building materials. The two methods have been exploited to characterize the deterioration status of the pillars of the church. For two of the investigated pillars direct information on the masonry structure have been provided by means of the extraction of a core and the endoscopie inspection of the hole left by the coring. The comparison between results provided by non invasive and indirect investigations with the data derived from the direct investigations : 1) put in evidence the great effectiveness of the two employed diagnostic methods, when used in an integrated way, for detecting cracks and in-homogeneities in the inner structure of masonry building elements; 2) helped in interpreting the radargrams and seismic tomographies, thus providing data useful for the diagnosis of the monument. Finally, with regard to the GPR prospecting, the results obtained by a standard processing and by an inverse scattering algorithm have been compared.