The SG of fiber-reinforced composites can be  represented as shown below.
Let the material properties of the fiber and matrix be:

Fiber: E,,11,,  =230" GPa" , E,,22,,  =15"GPa",G,,12,,  "=" G,,13,,  "=15GPa," G,,23,,  "=7GPa" 
 ν,,12,,=ν_13=0.200,ν,,23,,=0.0714

Matrix: E =4.0GP, ν=0.35 

Fiber volume of fraction is assumed to be 60%
The material properties are obtained from:
“Soden, P. D., Hinton M. J. and Kaddour, A. S., Lamina properties, lay-up configurations and loading conditions for a range of fibre reinforced composite laminates. Compos. Sci. Technol., 1998, 58(7), 1011”