Analysis of subsurface water content with integrated techniques

We propose a study of the problem of deterioration of stone buildings of cultural importance, integrating different non destructive techniques (microclimatic and Ground Penetrating Radar). It is well known in fact that this deterioration can be attributed to the presence of water and/or moisture in the porous material that occurs in water-damaged and humid buildings, due to poorly manufactured constructions and inadequate maintenance. The distribution of moisture within stone mainly depends on not suitable environmental condition and by the presence of wet buried structures in the ground. The microclimatic and Ground penetrating radar (GPR) surveys were carried out inside the Crypt of the "Cattedrale di Otranto” (Lecce, South Italy). The careful analysis of the 0.4 m spaced GPR parallel profiles, acquired in the Crypt, using a Sir2 GSSI radar system with a 500 MGHz antenna, allow us to distinguish the wet and moisture zone, so a subsurface and surface moisture variations map is obtained. Microclimatic and GPR data are in good agreement and suggest that an important channelling of moisture has origin in the subsoil.