Variable stiffness laminates

FIGURE 3 Variable stiffness laminate materials concept for producing large structural reconfigurations. 

Giirdal Z, Olmedo R. In-plane response of laminates with spatially varying fiber orientation variable stiffness concept. AIAA J 1993 31(4) 751—8. 

In addition, lamination can result in up to 18 elastic coefficients and increased deformational complexities, but the additional coefficients can all be derived from the four primary coefficients using the concept of rotation and ply-stacking sequence. These complications are the result of geometric variables. If the laminate is properly constructed, the in-plane stretching or stiffness properties can still be specified by four elastic coefficients. We shall consider laminates of this nature. 

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