The analysis of deformation and damage mechanisms induced by shallow tunnelling on masonrystructures is carried out using an integrated, geotechnical and structural, numerical approach based on two-dimensional finite-element analyses. The masonry construction, schematised as a block structure with periodic texture, is regarded at a macroscopic scale as a homogenised anisotropic medium. The overall mechanical properties display anisotropy and singularities in the yield surface, arising from the discrete nature of the block structure and the geometrical arrangement of the blocks. The soil ismodelled by means of a linear elastic-perfectly plastic model. The numerical analyses are performed assuming plane strain and plane stress conditions for the soil and the masonry structure, respectively. A displacement-controlled technique is adopted to simulate the tunnel construction, which produces settlement troughs in agreement with the empirical Gaussian predictions at different volume losses under free-field conditions. In order to test the numerical approach, a preliminary set of parametric analyses is carried out considering a simple masonry wall, characterised by different geometrical and mechanical properties, founded on a clayey deposit. Then, the case study of the Felice aqueduct in Rome (Italy), undercrossed by two tunnels of a new metro line, is considered. Significant differences are observed between the uncoupled analysis, where displacements predicted under free-field conditionsare simply applied at the foundation level of the structure, and the interaction-based one, the latter being characterised by a reduced amount of tensile plastic strain. Numerical results in terms of vertical displacements at the ground level and on the structure are found to be in good agreement with monitoring data, thus validating the numerical model for this class of soil-structure interaction problems

Cultural heritage constitutive materials can provide excellent substrates for microbial colonization, highly influenced by thermo-hygrometric parameters. In cultural heritage-related environments, a detrimental microbial load may be present both on manufacts surface and in the aerosol. In this study, bacterial and fungal colonisation has been investigated in three Sicilian confined environments (archive, cave and hypogea), each with peculiar structures and different thermo-hygrometric parameters. Particular attention has been paid to microorganisms able to induce artifacts biodeterioration and to release biological particles in the aerosol (spores, cellular debrides, toxins and allergens) potentially dangerous for the human health (visitors/users). Results provided information on the composition of the biological consortia, highlighting also the symbiotic relationships between micro (cyanobacteria, bacteria and fungi) and macro-organisms (plants, bryophyte and insects). The results of this integrated approach, including molecular biology techniques, are essential for a complete understanding of both microbial colonization of the cultural objects and the potential relationship with illness to human.

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The Virgin Hodegetria, located in the Cathedral of Santa Maria Nuova in Monreale, near Palermo (Italy), probably dating the first half of the 13th century, is one of the earliest examples of medieval panel painting in Sicily. A diagnostic campaign was carried out on the panel aiming to identify the constituting materials and the executive technique, as well as to assess the state of conservation for supporting the methodological choice of the restoration intervention. Both non-invasive (X-ray radiography, digital microscope, multispectral imaging, ED-X-ray fluorescence) and micro-invasive (polarised light microscopy, ESEM-EDX, ATR-FTIR spectroscopy and micro-Raman spectroscopy) analyses were performed. According to the results, the executive technique followed the 13th–14th-century Italian painting tradition. A complex structure was applied on the wooden support, consisting of a double layer of canvas and several ground layers of gypsum and glue-based binder. The underdrawing was made by a brush using carbonaceous black pigment. The original palette includes red ochre, red lead, azurite, carbon black and bone black. During the several restorations, mercury-based red, indigo, smalt blue, orpiment and synthetic mars were used. The original silver leaf of the frame was covered with red tin-based lake and subsequently regilded with gold leaf. Proteinaceous and oil binders were also detected.

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