PSI - Issue 14

N Jagannathan et al. / Procedia Structural Integrity 14 (2019) 864–871 Author name / Structural Integrity Procedia 00 (2018) 000–000

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2. Matrix crack evolution under bi-axial loading A 2p ply symmetric [0 o /90 o ]

s laminate with an arbitrary number of 0 o and 90 o orientation plies have been chosen in the present study. The laminate has a thickness t and length L . The general cracking pattern in such cross-ply laminate has been shown in Fig.1. Stress analysis based on the oblique coordinate shear lag model has been adopted. Detailed stress analysis methodologies can be found in Jagannathan et al. (2016). The stress analysis of cracked laminate has been carried out using commercial software MATHEMATICA ver 9.

ε xx

Matrix crack

ε yy

ε yy

L

Matrix crack in 0 o

x

z

ε xx

y

t

Fig. 1. Cracking of cross-ply laminate under bi-axial loading

2.1. Material properties and Weibull parameters

[0 o /90 o ] s laminate made of T300/934 CFRP material has been used in this study. The mechanical properties for the above material system have been experimentally obtained by Zhang et al. (1992) as shown in Table.1. Table 1. Material property for the laminate used in the current analysis

Property E 11 , GPa E 22 , GPa G 12 , GPa

Values

144.8

11.4 6.5 0.3 150

ν 12

Laminate length, mm Ply thickness, mm

0.132