Examples:

Example 4.4 : Calculate all the lamina engineering constants for an off-axis lamina of AS4/3501-6 Epoxy with fibre orientation of .

Solution:

We know that all the lamina engineering constants are either reciprocal of ratio of two compliance terms in global material directions. So, we obtain compliance terms in principal material directions and then we transform it into global directions with .

Unit of all terms is 1/MPa.

Now, for

Thus, carrying out matrix multiplications, we get

1/MPa

Using direct equations given above can also be used but this should be done only when one is confident of remembering these relations in terms engineering constants in principal material directions.