복합재료 적층 구조물에 대한 열-기계-점탄성 연성 거동예측을 위한 개선된 일차전단변형이론

초록

In this study, an enhanced first-order shear deformation theory is proposed to efficiently and accuratelypredict the thermo-mechanical-viscoelastic coupled behavior of laminated composite structures. To this end,transverse shearstress and displacement fields are independently assumed, and the strain–energy relationshipbetween these fields issystematically established using the mixed variational theorem (MVT). In MVT, thetransverse shear stress fields are obtained from the third-order zigzag model, whereas the displacement fields ofthe conventional first-order model are considered to amplify the benefits of numerical efficiency. Additionally,a transverse displacement field with a smooth parabolic distribution is introduced to accurately predict thethermal behavior of composite structures. Furthermore, the concept of Laplace transformation is newlyemployed to simplify the viscoelastic problem, similar to the linear-elastic problem. To demonstrate theperformance of the proposed theory, the numerical results obtained herein were compared with those availablein the literature.

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