orthotropic lamina properties 1

[Mike20132020]

Dear

i have lamina with orthotropic properties how i can derive an expression for Gxy (equivalent shear stress) in terms of E1, E2,v12,G12, and theta ????

where: E1: is the elastic modulus at the fiber direction
E2: elastic modulus at transverse direction
v12: is the main possion ratio

please advise since i am working on research and i can't obtain the equivalent shear modulus ?

 

[compositesFEAguru]

Mike - This calculation gets rather complex and probably can't be expressed too easily in a single equation. I would look into obtaining a composite laminate analysis software package.

Firehole Composites

http://www.firehole.com

 

[ESPcomposites]

(1/Gxy) = 4(m^2)(n^2)(1+v12)/E1 + 4(m^2)(n^2)(1+v21)/E2 + [(m^2 - n^2)^2]/G12
v12/E1 = v21/E2
m = cos(theta)
n = sin(theta)

From "Engineering Mechanics of Composite Materials", Daniel and Ishai, 2nd edition, p. 84.
The Jones book probably has it too.

Brian

http://www.espcomposites.com