PSI - Issue 78

Noemi Di Rienzo et al. / Procedia Structural Integrity 78 (2026) 1474–1481

1479

= n n 2 h f k L

(3)

In the following the same expression type will also be considered for continuous bridges, where L will be the average span length. In Error! Reference source not found. b, the first two flexural frequencies as determined experimentally for the dataset described in Section 2 are compared to the geometry parameter ℎ/ 2 . The linear regression is also displayed together with the corresponding coefficient of determination R 2 . Values higher than 0.8 are shown in all cases except for the first frequency of continuous decks. It must be said that in the case of continuous deck the use of the average span length as main geometrical parameter may not be appropriate, especially in the case of irregularity in the span lengths (see for instance Voigt Drive or Connecticut Bridge in Table 1).

Fig. 3. Linear regression of the relationship between experimental frequencies and geometrical parameter h/L2: (a) first frequency, and (b) second frequency; SS: simply supported, C: continuous bridges. The final empirical-analytical coefficients for Eq. 3 evaluated in this work are:

ss

1925 6135 1656 2748

k k k k

m/ s m/ s m/ s m/ s

= =

1

ss

2

(4)

c

= =

1

c

2

where the superscripts ss and c respectively refer to simply supported and continuous decks. 4. Conclusions and future developments

In this work, simplified analytical-empirical expressions for the prediction of the first two frequencies related to vertical bending of simply supported and continuous bridge decks have been derived based on some experimental data