Abstract: By extending the classical laminate theory to the cross section of a corrugated plate with sinusoidal profile, the membrane, bending and membranebending coupling stiffness terms of the corrugated plate are obtained in the form of analysis formulae. Techniques are presented for implementing these stiffness terms into the material bulk data cards of MSC/NASTRAN and for modeling a corrugated plate with a single plane of shell elements. The methods given in this article are applied to obtain static solutions of a composite wing box with corrugated webs. The displacements and strains at the gauge sensor locations are acquired. Compared with the results acquired by traditional finite element analysis, the results obtained in this article agree better with those obtained by the gauge sensors. When the structure is subjected to pure bending load, the average relative errors of computed displacements and strains decrease to 5.2% and 4.1% from 9.1% and 17.4 %, respectively; when the structure is subjected to bending and twisting loads, they decrease to 6.0% and 5.7% from 10.5% and 18.3%, respectively.

Key words: composites, corrugated plate, structure stiffness, structure strength, finite element modeling