PSI - Issue 78

Maria Zucconi et al. / Procedia Structural Integrity 78 (2026) 839–844

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building height varies parametrically from 1 to 6 stories. The foundation footprint is kept constant at 300 m² (15 m × 20 m), enabling the isolation of height-dependent effects on loss estimation. The structural system consists of a moment-resisting RC frame with full-height unreinforced masonry infill panels at each perimeter bay. These infills are considered non-structural but contribute significantly to the economic loss when damaged, particularly at the ground floor where tsunami actions are concentrated. This configuration offers a balance between simplicity and representativeness, allowing for controlled variation of the two key parameters investigated in this study: • the number of stories, affecting the total floor area and cost normalization; • the length of damaged infill walls at the ground level, varied to simulate different extents of tsunami induced impact. This synthetic model forms the basis for the following sensitivity analysis, in which the repair cost ratio (Cr%) is evaluated as a function of the aforementioned parameters under different damage scenarios (DSt1 and DSt2). 4. Sensitivity Analysis of Repair Cost Ratio The parametric configuration described above was used to investigate how variations in building height and damage extent affect the Cr% under tsunami-induced non-structural damage. The analysis was performed for the two damage states involving infill walls only: DSt1, related to minor cracking, and DSt2, corresponding to more severe degradation such as out-of-plane failure and damage to openings and utilities. For each scenario, the number of perimeter bays damaged at the ground story was varied from 1 to 14 (full perimeter), while the number of stories ranged from 1 to 6. The results show that Cr% is highly sensitive to both parameters, with more pronounced effects in low-rise buildings. In Figures 1 and 2 Cr% are plotted on the vertical axis, while the number of stories is reported on the horizontal axis. Each curve corresponds to a different extent of ground-floor infill wall damage, expressed as the number of affected bays. Figure 1 presents the results for DSt1. In the case of a single-story building, Cr% exceeds 11% when all 14 bays are damaged, while it remains below 2% for six-story buildings, even under the same damage scenario. The influence of the number of damaged bays is nonlinear: increasing from 1 to 6 bays causes a notable rise in Cr%, but the growth becomes progressively less significant beyond 10 bays.

10 15 20 25 30 35

DSt1 Damaged 14 bays Damaged 10 bays Damaged 6 bays Damaged 3 bays Damaged 1 bay

Repair cost ratio [%]

0 5

1

2

3

4

5

6

N. of Stories

Figure 1 Repair cost ratio (Cr%) for DSt1 as a function of the number of stories with respect to the number of damaged bays.