Homework # 6

Problem #1 (For ALL students): 10 Points
Consider a [± 30 / 0]S laminate is subjected to a combined loading
0
of M x = 25 Nm / m,
and
?T = -150 C

Material properties:
E1 = 155GPa
E2 = 12.1GPa
?12 = 0.248
G12 = 4.40GPa h = 0.15mm
X t = 1500MPa
X c = 1250MPa
Yt = 50MPa
Yc = 200MPa
S = 100MPa
a = -0.018 × 10-6 / 0C
a = 24.3 × 10-6 / 0C
ß = 146 × 10-6 / % M
ß = 4770 × 10-6 / % M
ˆ T = 97.2 N / m/ 0C
ˆ T = 232 N / m/ 0C
ˆ M = 36600 N / m / %
ˆ M = 49400

N / m / %
Find the lamina failure status (safe or failed ) along with failure mode of the laminate using maximum stress criteria.

Problem #2 (For All students): 10 Points
Consider a [± 30 / 0]S laminate is subjected to a combined loading of
0
M x = ±mx Nm / m, and
?T = -150 C

Material properties:
E1 = 155GPa
E2 = 12.1GPa
?12 = 0.248
G12 = 4.40GPa h = 0.15mm
X t = 1500MPa
X c = 1250MPa
Yt = 50MPa
Yc = 200MPa
S = 100MPa
a = -0.018 × 10-6 / 0C
a = 24.3 × 10-6 / 0C
ß = 146 × 10-6 / % M
ß = 4770 × 10-6 / % M
ˆ T = 97.2 N / m/ 0C
ˆ T = 232 N / m/ 0C
ˆ M = 36600 N / m / %
ˆ M = 49400

N / m / %

Find the moment Mx required to cause first ply failure (FPF) in the laminate using Tsai-Wu criteria (with Von
Mises approximation).

N

1

1

2

N

N

x

y

N

y

2

N

1

x

x

1

2

N

N

x

y

N

y

/ 0C
ˆ M = 36600 N / m / %
ˆ M = 49400

N / m / %

Find the moment Mx required to cause first ply failure (FPF) in the laminate using Tsai-Wu criteria (with Von
Mises approximation).

N

1

1

2

N

N

x

y

N

y

2

N

1

x

x

1

2

N

N

x

y

N

y

Yt = 50MPa
Yc = 200MPa
S = 100MPa
a = -0.018 × 10-6 / 0C
a = 24.3 × 10-6 / 0C
ß = 146 × 10-6 / % M
ß = 4770 × 10-6 / % M
ˆ T = 97.2 N / m/ 0C
ˆ T …