Understanding the Mechanics of Composites: Stress and Strain Transformations

[samson07]

Does anyone know how to even start this problem.. :(
I seriously have no idea...spent like few hours to find this out on the library and no luck...
Please help a poor guy out...I aint smart enough for this...

 

[Jus]

Hi Samson07,

I think this needs to be tackled from a strain perspective as well as a stress perspective as the material is a laminate. For composites, you need to perform both on-axis properties and off-axis properties in order to fully analyse the laminate.

Try looking under 'Stress and Strain Transformations in Composites'. This should tell you a bit more about it and it will also explain the stiffness matrix that you have presented in your attachment.

Good luck...

Kind Regards,

Jus