Page 229 - Mechanics Analysis Composite Materials

214 Mechanics and analysis of composite materials

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Fig. 4.88. Interstage composite lattice structure. Courtesy of CRISM.

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Fig. 4.89. A composite lattice shear web structure.

k
A12 = A21 = A44 = Bj sin2 4j cos2 4j,
j= 1
k k
A44 = Cj cos2 $,, A55 = Cj sin2 4j ,
j= I j= 1
where Bj = E,Sj/aj and Cj = GjSj/aj, where Ej and G, are the modulus of elasticity
and the shear modulus of the ribs materials, Sj the ribs widths, and uj are the ribs
spacings (see Fig. 4.90).

4.8. Spatially reinforced layers and bulk materials

The layers considered in the previous sections and formed of unidirectionally
reinforced plies and tapes (Sections 4.24.5 and 4.7) or fabrics reinforced in the layer
plane (Section 4.6) suffer from a serious shortcoming - their transverse (normal to