Mechanical decay and degradation of marble slabs

The authors conducted studies on mechanical decay processes of stone materials, mainly white Carrara marble, used in historical buildings and monuments. The examined processes are mainly referred to the mechanical decay and degradation of marble slabs due to bending phenomena.These time-dependent deformating phenomena are connected to the geotectonic and geomorphologic history, to the effects of new environmental conditions and to the new geometry of the stone elements. The most relevant parameter, represented by the tectono-metamorphic history of any marble, affects the main microstructural characteristics of the material and, consequently, its mechanical decay and degradation. This paper presents the methodologies used for evaluating deformation on selected dated slabs, the sampling strategy for a correct comparison with quarry samples, the results of the artificial ageing tests performed on numerous samples of Carrara marbles (Gioia quarry) and the relationship of the physical characteristics with the mechanical parameters.