PSI - Issue 52

5

Valerio Acanfora et al. / Procedia Structural Integrity 52 (2024) 340–347 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

344

Figure 5: Comparison between model with no damage and the model with intra-laminar damage, for the four elements through thickness model.

It has been observed that intralaminar damage is more noticeable with the use of eight elements due to the reduced assembly of specimen plies. Tensile cracks are generated when in-plane normal stresses exceed the transverse tensile strength of the ply. Matrix cracks are initially induced in the topmost layer impacted by the projectile due to the high, localized contact stresses. Subsequently, damage progresses in a downward direction, resulting in a pine tree pattern (Figure 6 and Figure 7).

Figure 6: Intra-laminar damaged caused on the eight elements through thickness model.