PSI - Issue 60

Amardeepa KCS et al. / Procedia Structural Integrity 60 (2024) 60–74 Amardeepa KCS/ Structural Integrity Procedia 00 (2023) 000–000

68

9

5.2. Yamada-Sun's failure criterion used for checking the safety of composite plies against in-plane stresses:

2

2

   

   

S      L



   

1.0

Ys =

Eq-(3)



12

S

Where, σ 11 = Normal stress in lamina along fiber direction τ 12 = Shear stress in lamina S L = Allowable stress in lamina along fiber direction (X t = 520 N/mm

2 and X

c = 506 N/mm

2 )

S = Allowable in-plane shear stress in the lamina (s = 56.3 N/mm 2 ) The Axial Force (AF) acting along the axis of the 1D CBAR element and the transverse forces along Plane 1 shear and Plane 2 shear are resolved for the applied enforced displacement, as shown in Figure 15. As discussed in Section 4, the 1D CBAR elements are numbered in chronological order for one complete row of the FE model starting from 1 up to 1D element number 131 of 1D CBAR elements as shown in Figure 16 (a) for its easy identification and precise location. The standalone FE model is a symmetry model; hence a typical numbering pattern is illustrated for envisaging the numbering pattern as shown in Figure 16 (b)&(c) at zone 2. Similarly, the numbering pattern continues for 25 rows for layers (1-2), (2-3), and (3-4). As the data is enormous to discuss, Figures (17), (18)& (19) show a typical distribution of the forces along Axial Force (AF), Plane 1 shear, and Plane 2 shear for the resolved force components of points 1 to 4 for one complete row of elements based on the axial and shear force diagrams shown in Figure 15.

Fig 15 Typical ID CBAR element axial shear force components resolved to show the force equilibrium.

(a) Numbering of ID CBAR element for 1 Row of elements between layers 1-2

(b) zone 2

(c) 3D view of 1D elements at zone 2

Fig 16 (a) Numbering of ID CBAR element for 1 Row of elements between layers 1-2, (b) zone 2, (c) 3D view of 1D elements at zone 2

6. Results and Discussions Figure 20 shows the maximum displacement of the L angle is 1.23 mm along the (Z-axis) ), at the free edge, but at