PSI - Issue 13

Emre Özaslan et al. / Procedia Structural Integrity 13 (2018) 535–541 M.A. Güler et al./ Structural Integrity Procedia 00 (2018) 000 – 000

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Table 3. Open hole test specimens

Specimen Name

W (mm)

L(mm)

D(mm)

OHT1 OHT2 OHT3 OHT4 OHT5 OHT6

36 36 36 36 48 24

250 250 250 250 250 250

3 6

10 12

8 4

3. Finite Element Analysis

The finite element analyses were performed using commercial code Abaqus 6.14. Full integration 4 node shell S4 elements were used for all cases. There were 3233 elements and 3398 nodes in finite element model. Because of the symmetric and balanced laminate stacking sequence, quarter model with appropriate symmetry boundary conditions was performed. Loading, boundary conditions and mesh are shown in Fig. 2.

Fig. 2. Finite element model of the test specimen

4. Point Stress Criteria (PSC)

Point stress criteria (PSC) was proposed by Whitney and Nuismer (1974) to predict the strength of an anisotropic plate with a circular hole. In this method, plate final failure occurs under uniaxial tension loading when the stress at a certain distance from the hole edge characteristic distance 0 ( ) d , reaches to unnotched plate strength 0 ( )  (see Fig. 3). It is concluded from the definition of PSC method that unnotched strength of laminate and characteristic distance should be known to predict notched strength.

Fig. 3. Schematic view of PSC method