PSI - Issue 84

Gianluca Centofanti et al. / Procedia Structural Integrity 84 (2026) 1339–1346

1345

Figure 6. Finger joints between the contiguous spans in the S. Onofrio Viaduct.

Table 3. First ten modal parameters identified for the S. Onofrio Viaduct by means of COV-SSI algorithm for the 6 sub-groups.

Subgroup: Piers

Subgroup: Span 2

Subgroup: Span 3

#

#

#

Freq. [Hz]

Damping [%]

Cluster size

MPC [%] 94.2 87.2 97.9 90.0 88.2 94.8 93.6 99.1 96.6 95.9 MPC [%] 99.9 98.9 88.2 97.9 99.9 100 94.6 89.5 99.9 92.1

Freq. [Hz]

Damping [%]

Cluster size

MPC [%] 98.6 94.1 85.8 98.9 97.3 100 100 99.9 97.2 99.1 MPC [%] 99.3 98.1 99.7 99.3 100 99.8 89.8 97.0 99.9 95.3

Damping [%]

Cluster size

MPC [%] 99.0 87.2 97.7 99.6 90.1 100 54.8 99.5 91.3 99.7 MPC [%] 97.2 92.0 100 53.4 99.0 99.9 99.8 99.9 100 99.9

Freq.[Hz]

1 3.75 2 4.229 3 4.428 4 4.991 5 5.189 6 5.551 7 6.02 8 6.97 9 7.717 10 12.755 1 2.733 2 3.729 3 4.337 4 4.359 5 4.833 6 5.131 7 5.607 8 10.693 9 15.483 10 18.608 # Freq. [Hz]

1.41 4.44 2.21 3.17 2.05 1.11 4.87 1.81 4.14 2.26 7.44 4.42 1.78 1.64 1.58 0.92 0.79 1.48 1.34 1.54

33 31 26 32 28 37 41 36 20 32 48 26 56 33 56 56 35 22 40 56

1 2.718 2 3.746 3 4.167 4 4.402 5 4.616 6 5.006 7 5.356 8 6.937 9 7.759 10 13.966 1 2.445 2 2.818 3 4.145 4 4.442 5 4.848 6 5.148 7 10.277 8 12.884 9 14.672 10 15.183 # Freq. [Hz]

6.04 1.71 3.60 1.16 1.43 1.23 1.35 1.86 2.36 1.27 8.88 8.02 1.73 2.35 1.21 1.82 1.99 1.86 1.84 1.02

52 20 28 56 56 56 49 48 23 34 26 32 56 43 56 53 31 20 31 48

1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 #

2.683 3.633 4.404 4.601 4.995 5.341 5.975 6.96 10.28 2.637 3.731 3.912 4.000 4.774 4.865 5.154 5.16 5.549

7.02 8.11 1.29 1.40 1.20 1.44 2.15 2.00 2.69 1.12 7.46 1.42 1.62 8.23 0.72 1.36 1.34 2.60 1.24 2.22

56 24 56 56 47 56 24 35 44 47 28 20 56 24 29 21 20 32 56 33

10 15.56

Subgroup: Span 4

Subgroup: Span 5

Subgroup: Span 6

Damping [%]

Cluster size

Damping [%]

Cluster size

Damping [%]

Cluster size

Freq.[Hz]

10 14.897

Figure 7. Geometric descriptions of the identified mode shapes, together with MAC coefficients, for the S. Onofrio Viaduct.