IMAGING ED ANALISI 3D DELLA STRUTTURA POROSA DEL TUFO GIALLO NAPOLETANO:UN CONTRIBUTO ALLO STUDIO DEL DEGRADO ARCHITETTONICO A CASTEL NUOVO

Façades of Castelnuovo made with bricks of Tufo Giallo Napoletano (TGN) show, among other types of stone decay, a certain extent of black crusts. Such a kind of degradation, independently from its origin is affected by the typical porous structure of that rock material. Multiscale scanning of a samples of TGN from the southwestern façade of the castle has been carried out by means of X-ray microCT in order to reconstruct images of its natural and degraded inner structure. The 3D image analysis algorithm of "successive opening" has then been applied to determine the size distribution and the connectivity of the outer connected pores of the TGN. The crust thickness distribution and its development inside the pores under the surface of the rock material has also been evaluated. Results allowed to recognize X-ray microCT as a useful technique of investigation of stone decay in the framework of a multidisciplinary approach aiming at addressing the restoration treatments.