PSI - Issue 78

Somayeh Gholami et al. / Procedia Structural Integrity 78 (2026) 1459–1465

1463

Table 1. Main geometric and construction features of the five selected case-study buildings in Casertavecchia.

Wall area(m 2 ) in the weakest floor

Floor Height (avg)(m)

ϐ (weakest floor)

μ(weakest floor)

Base Wall Thickness(m)

ξ

ζ

ID no.Floors

x

y

x

y

x

y

x y x y

213sub 4 3

2.45

0.65 0.65 0.55 0.65

3.8 8.1 1.25 1.08 0.8 0.85 1 1 0.8 0.8 19.9 27.8 1.25 1.25 0.84 0.86 1 1 0.8 0.8 10.6 11.7 1.25 1.15 0.83 0.91 1 1 0.8 0.8 9.7 9.25 1.25 1.25 0.87 0.85 1 1 0.8 0.8 8.5 22.9 1.25 1.17 0.85 0.8 1 1 0.8 0.8

213 217 214 209

2 3 2 1

3

3.3

3

2.9

0.5

e

c

d

a

b

Fig. 2 . Architectural floor plans of the surveyed historic buildings in Casertavecchia. (a)213sub 4, (b) 213, (c) 217, (d) 214, (e) 209

4. Vulnerability assessment 4.1. Assumptions for the assessment

Mechanical parameters of masonry (i.e., masonry density and design shear strength) , were defined according to typical values defined in Italian Standards (Ministero delle Infrastrutture e dei Trasporti) for soft stone masonry. They were: • Masonry density: ρ =1400 kg/m³; • Design shear strength: τ 0d =0.06MPa (adjusted by accounting for a confidence factor FC =1.35). For each building, the in-plane shear capacity was calculated for all floors and both principal directions, and the lowest value corresponding to the most vulnerable floor-direction combination was selected as the global base shear capacity. The spectral acceleration capacity ( a LSLS ) was then derived by incorporating the total seismic mass, behavior factor ( q ), and dynamic coefficients (e.g., modal participation and mass distribution, e* ) . The seismic demand was defined through a reference return period T R , which depends on: the nominal life V N =50 years, and the use class coefficient C U =1, corresponding to Class II (ordinary buildings). These give a reference period: VR=VN ⋅ CU =50 years. According to NTC2018 (Ministero per le Infrastrutture e i Trasporti, 2018), the seismic action for verification at the Life Safety Limit State ( LSLS ) must correspond to a 10% exceedance probability over the reference period. The resulting return period is computed as: TR=VR/ln (1−0.10) ≈ 475 years. Site-specific spectral parameters ag =1.005, F0 =2.45, TC =0.44 s, were obtained from the NTC2018 hazard maps for Casertavecchia, using a spatial resolution of 5 km.