PSI - Issue 78

Matteo Tatangelo et al. / Procedia Structural Integrity 78 (2026) 404–411

409

a)

b)

c)

CC3 S=100m

CC2 S=100m

CC1 S=100m

Fig. 3. Reliability analysis of an existing bridge with degradation law by considering the target reliability indexes with = 100 2

b)

a)

c)

Fig. 4. R.C. half-joint: a) Section details; S&T-Ms b) model a , and c) model b (EN 1992-1-1, 2004)

4. Life cycle management of RC half-joint In the following a time-dependent reliability assessment of a RC half-joint (RC Gerber saddle) is performed by applying the procedure presented in Sect. 3 according to Level 2 method. In order to perform the assessment, the RC half-joint (Fig. 4.a) of the “ Musmeci ” Bridge in the Italian city of Potenza is considered (Ponzo et al., 2013). The R.C. half-joint forms discontinuous zones in the deck, which is schematized with a double-supported beam of length equal to 10.38 m (Ponzo et al., 2013). The beam cross-section (Fig. 4.a) measures 0.45 m width (B) and 1.05 m depth (H), with a 0.05 m (cov) concrete cover. The nib have a depth (h) equal to 0.50 m and a width in the beam (a) of 0.40 m. As for the steel reinforcing bars, they are summarized in the RC half-joint section in Fig. 4.a. The half-joints (or Gerber saddle) constitute a classic example of rapid changes in cross-section in a beam and stubby elements, therefore they are commonly treated with Strut and Tie Models (S&T-Ms). The latter are used for the design of RC elements that cannot be schematized as slender solids or Saint Venant beams. In detail, the model considers the resistant structural mechanism as a reticular truss, with tensioned and compressed rods, where the compressed rods (struts) are realized by the concrete, while the tensioned rods (tie rods) consist of the reinforcement. The assessment of RC half-joints differs from how S&T-Ms would be used in the design of new construction, since one should comply with the provided reinforcement layout of the structure under assessment, such as the selection of the preferred concrete quality and strength (Desnerk, Lees & Morley, 2018). Two different models