The Assessment of Wall Connections in Pompeii Plastered Buildings using GPR

The seismic behaviour of masonry buildings is strongly influenced by the effectiveness of connections between orthogonal walls. In Pompeii, many walls are poorly or completely disconnected; however, direct inspection is generally not feasible due to the presence of thick plaster and frescoed surfaces. This study evaluates the feasibility of using Ground Penetrating Radar (GPR) as a non-invasive technique to identify the presence and effectiveness of corner bonding in Pompeian buildings. Preliminary tests confirmed that a high-frequency 3 GHz GPR antenna, required to achieve the spatial resolution for reconstructing internal wall geometry necessary to investigate the wall-to-wall connections, is capable of penetrating the full wall thickness. Subsequently, selected connections were investigated in the House with the Garden in Pompeii through a combination of vertical and horizontal GPR profiles. The results show that absent, partial and effective connections between orthogonal walls can be distinguished. The study confirms that the proposed GPR approach represents a reliable and non-destructive tool for assessing masonry connections also in plastered archaeological structures, providing valuable information to support seismic vulnerability assessment and structural analysis.