Stress Function-Based Interlaminar Stress Analysis of Composite Laminates under Complex Loading Conditions

응력함수에 기초한 복합 하중하의 복합재 적층판의 층간응력 해석

  • 김흥수 (동국대학교 기계로봇에너지공학과) ;
  • 김정윤 (대구가톨릭대학교 기계자동차공학부) ;
  • 김진곤 (대구가톨릭대학교 기계자동차공학부)
  • Received : 2009.10.09
  • Accepted : 2010.03.03
  • Published : 2010.06.30

Abstract

Interlaminar stresses near the free edges of composite laminates have been analyzed considering wall effects. Interface modeling of bonding layer was introduced to explain the wall effect. Using Lekhnitskii stress functions and the principle of complementary virtual work, the interlaminar stresses were obtained, which satisfied the traction free boundary conditions not only at the free edges, but also at the top and bottom surfaces of laminates. The interface modeling provides not singular stresses but concentrated finite interlaminar stresses. The significant amount of reductions of stresses at the free edge are observed compared to the results without interface modeling. The real stress state can be predicted accurately and the results demonstrate the usefulness of the proposed interface modeling for the strength design of composite laminates.

Keywords

References

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