Composites Research

The Korean Society for Composite Materials (한국복합재료학회)
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Post-buckling Behavior and Vibration Characteristics of Patched Reinforced Spherical Composite Panels

패치로 보강된 구형 복합재료 패널의 후좌굴 거동 및 진동 특성해석

  • Published : 2001.08.01
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Abstract

The finite element method based on the total Lagrangian description of the motion and the Hellinger-Reissner principle with independent strain is applied to investigate the nonlinear behavior and vibration characteristics for patched reinforced laminated spherical panels. The patched elements are formulated using variable thickness at arbitrary point on the reference plane. The cylindrical arc-length method is adopted to obtain a nonlinear solution. The post-buckled vibration is assumed to be small amplitude. The effect of patch in the spherical shell Panel is investigated on the nonlinear response and the fundamental vibration characteristics. The present results show that the load-carrying capability can be improved by reinforcing patch. The fundamental frequency of patched panel is lower than that of equivalent shell panel. However, the fundamental frequency of patched panel does not decrease greatly due to the increase of nonlinear geometrical stiffness under loading.

토탈 라그랑지안 방법과 변형율을 가정한 Hellinger-Reissner 원리에 기초한 유한요소법을 이용하여 패치로 보강된 구형 복합재료 쉘의 후좌굴 거동 및 진동 특성을 살펴보았다. 패치 요소는 따로 다른 유한요소를 사용하지 않고 쉘의 중앙면과 다른 기준점을 잡아 두께 변수를 택하여 정식화를 하였다. 비선형 해법으로 원통형 호-길이법을 적용하였고, 후 좌굴 진동은 미소 진폭을 갖는다고 가정하였다. 구형 쉘 패넬에서 패치가 비선형 거동 및 진동수에 미치는 영향을 고찰하였고, 그 결과 패치는 하중지지도를 개선시키킨다. 패치로 보강된 패널의 1차 고유진동수는 등가 패널에 비하여 낮으나, 하중을 받는 경우 1차 고유진동수는 급격히 감소하지 않았다.

Keywords

References

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