PSI - Issue 28

Paolo Ferro et al. / Procedia Structural Integrity 28 (2020) 19–25 Ferro, P. and Berto, F / Structural Integrity Procedia 00 (2019) 000–000

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3. Critical radius assessment The geometry of the adhesively bonded butt joint follows that of Standard ISO 6922. In particular, the joint diameter is 15 mm while the adhesive thicknesses (h) modelled are: 0.12, 0.4, 2.0, 7.5 mm. By taking advantage of the load and geometry symmetry, only a quarter of the geometry has been modelled using PLANE 183 elements and axisymmetric condition. The size of the smallest element was about 1.6ꞏ10 -5 mm (Fig. 2).

Fig. 2. A detail of the mesh near the singularity point A

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 0.00E+00 5.00E-03 1.00E-02 1.50E-02 2.00E-02 2.50E-02 3.00E-02 σ σ σ

σ /σ

r (mm)

Fig. 3. Asymptotic stress distribution at steel-epoxy interface (θ = 0), adhesive side. σ 0 = 1 MPa, nominal applied stress; h = 0.12 mm