PSI - Issue 78

Eugênio Moreira et al. / Procedia Structural Integrity 78 (2026) 1967–1974

1969

Nonetheless, coupling realistic thermal e ff ects with CDP-based seismic vulnerability assessment remains a key research need. For heritage structures, such as medieval walls subject to persistent thermal cycling, this integration is essential to understanding pre-conditioning impacts on seismic response and for developing reliable retrofitting strategies.

3. Case Study: Gubbio’s Medieval Wall

Gubbio’s medieval wall, completed in the 14th century after multi-phase construction probably initiated in the 12th century, exemplifies heterogeneous multi-leaf stone masonry resulting from successive architectural interventions (Micalizzi, 2009). The structure encloses 2.8 km of city perimeter, with heights up to 12.0 m and thicknesses from 0.5–3.0 m (Curulli et al., 2020; Cavalagli et al., 2019). Wall composition includes limestone, travertine, and sandstone masonry bound by lime mortars containing quartz and calcite aggregates, yielding pronounced thermal and mechanical property variability (Carvalho et al., 2018). Conservation states di ff er across five main wall zones: Zone 1 (Forte di Parco Ranghiasci) exhibits earth accumu lation and upper wall degradation; Zone 2 (Cassero), replaced by a 19th-century concrete retaining wall, preserves only foundations; Zone 3 (Torre) retains original structure; Zones 4-5 (Porta S. Ubaldo and Bughetto) have been re stored (Fig. 1). These varying conditions result in distinct local boundary environments, providing an ideal context for integrated thermal-mechanical assessment.

Fig. 1. Ancient wall boundaries, structural zones, and monitoring station locations. After Curulli et al. (2020); Sisani (2010)

Within the HERACLES project (CORDIS, 2016), Gubbio’s wall was instrumented with three monitoring stations (Fig. 1) equipped with monoaxial inclinometers and thermo-hygrometers acquiring 10-minute interval data (Cavalagli et al., 2019), providing a robust baseline for model validation. Integrated assessment leveraged advanced investiga tions: GPR for subsoil profiling (Catapano et al. (2018)), InSAR (2011–2016) for deformation, and laboratory anal yses (XRD, SEM, thermogravimetry) for precise material parameterization. Monitoring revealed seasonal thermal inclination coupling and underscored thermal pre-conditioning e ff ects on wall behavior, supplying essential data for validating the thermal-mechanical vulnerability framework (Padeletti and HERACLES Consortium Sta ff 2019; Cu rulli et al. 2020).