PSI - Issue 78

Franco Braga et al. / Procedia Structural Integrity 78 (2026) 2184–2191

2190

5.2. Comparison between code-prescribed actions (NTC08) and recorded actions (AMTS) Referring to the NTC08 spectrum, Figure 9 shows that in the E-W direction the spectral acceleration is higher than that of the AMTS E-W spectrum, whereas in the N-S direction the opposite occurs.

Fig. 9. Comparison between project, current and real actions

5.3. Comparison in terms of Global Reactions a LOAD COMBINATION Tx (E-O) Ty (N-S)

b

T z,max (vert)

T z,,min (vert)

T orizz =

(T x

2 +T

2 ) 0.5

y

kN kN kN kN 3980 2146 17499 16388 2153 3959 17476 16411 5238 3334 19482 14405 3519 6801 19410 14477 2487 2778 23255 10632

kN

4522 4507 6209 7657 3729

SLV1 (NTC08) SLV2 (NTC08)

AMTS1 AMTS2 AMTS3

Fig. 10. Comparison of directionally combined horizontal shears (Torizz) a) table of values b)graphic comparison

Fig. 10 shows the global seismic shear forces at the base of the building caused by the seismic action as defined by NTC08 and as recorded instrumentally at the Romolo Capranica School (AMTS). It can be noted that: • the shear forces obtained using the AMTS spectra are more severe than those obtained with the NTC08 spectra; for example, the AMTS2 combination exhibits an N-S shear 1.7 times higher than the SLV2 combination. The directionally combined horizontal shears are consistently much higher for the AMTS combinations. • the vertical reactions for the AMTS components show significant fluctuations, both increasing and decreasing. 5.4. Comparison in terms of capaciry/demand ratio To evaluate the severity of near-fault earthquakes, such as the one on August 24, 2016, a seismic retrofitting intervention was simulated on the building to align it with NTC08, following the procedure outlined below: 1) Dynamic analysis using a response spectrum, applying NTC08-prescribed actions 2) Shear capacity checks of the masonry panels, identifying those not meeting the requirements; in this study, only in-plane shear checks were performed 3) Application of FRP strip reinforcement to the deficient panels to achieve a safety factor ≥ 1. 4) Dynamic analysis with a response spectrum using the AMTS-recorded actions from the night of August 24,