Aspects of Application: Free Edges, Laminate Holes, and Optimal Topology

  • Wilfried Becker
  • Heiko Engels
  • Wilfried Hansel
  • Jan Lindemann
Part of the International Centre for Mechanical Sciences book series (CISM, volume 448)


The following chapter addresses some aspects that appear in a very particular manner for laminate structures and which are important for the real-life application. The clear understanding and the sound analysis of these aspects is essential to prevent undesired effects or consequences and to reveal the full potential that is possible with a well-aimed laminate design. In this sense the first section presents the so-called laminate-free edge effect, which means the occurrence of high localized interlaminar stresses in the vicinity of free edges. Beyond this the subsequent section is devoted to the respective effect at free laminate corners. Next, stress concentrations around holes and possibilities of their analysis are addressed. In order to reduce the stress concentrations around holes and in order to recover sufficient effective strength then hole reinforcements by laminate patches are considered. Eventually, in view of lightweight requirements a methodology is presented to minimize the total weight of laminate structures by means of a well-aimed layerwise topology optimization.


Optimal Topology Energy Release Rate Free Edge Stress Concentration Factor Laminate Plate 
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Copyright information

© Springer-Verlag Wien 2003

Authors and Affiliations

  • Wilfried Becker
    • 1
  • Heiko Engels
    • 1
  • Wilfried Hansel
    • 1
  • Jan Lindemann
    • 1
  1. 1.Institute of Mechanics and Control EngineeringUniversity of SiegenSiegenGermany

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