Simple boundary element analysis of laminated composite structures

Abstract Composite materials have been widely used in industries for several years owing to their capability to perform better than homogeneous isotropic materials. Numerical tools like finite element method are efficiently used for analysis of structures made of composite materials. However, for complex shapes or geometries of structures, it becomes uneconomical (computational resource wise) to use Rayleigh-Ritz based finite element analysis. An unique Trefftz based finite element has been developed in this article to efficiently fill the gap in the above mentioned scenario. Hybrid-Tefftz finite element method’s flexibility to use arbitrary shaped elements comes handy in modelling complex geometries. The developed hybrid-Trefftz finite element approach has been used on symmetric angle-ply laminated composite plate and the obtained results have been compared with bench mark solutions. The present method proposes an approach for development of hybrid-Trefftz type finite elements, by which analysis of antisymmetric structures is also possible, an area of research which has been less explored by such approach as revealed from survey of available open literature.

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Test and Finite Element Analysis on Compression after Impact Strength for Laminated Composite Structures of Unidirectional CFRP

Composites Research ◽

10.7234/composres.2016.29.6.321 ◽

2016 ◽

Vol 29 (6) ◽

pp. 321-327

Author(s):

Jae-Seok Ha

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Impact Strength ◽

Composite Structures ◽

Laminated Composite ◽

Element Analysis ◽

Compression After Impact ◽

Laminated Composite Structures

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A model for fast delamination analysis of laminated composite structures

Rakenteiden Mekaniikka ◽

10.23998/rm.82730 ◽

2020 ◽

Vol 53 (2) ◽

pp. 67-84

Author(s):

Harri Katajisto ◽

Petri Kere ◽

Mikko Lyly

Keyword(s):

Composite Structures ◽

Laminated Composite ◽

Strain Energy Release ◽

Element Analysis ◽

Geometrically Nonlinear Analysis ◽

Shell Elements ◽

Cycle Times ◽

Modeling Methodology ◽

Laminated Composite Structures ◽

Cohesive Zone Elements

Delamination is one of the major failure mechanisms for composites and traditionally the simulation requires high expertise in fracture mechanics and dedicated knowledge of the Finite Element Analysis (FEA) tool. Yet, the simulation cycle times are high. Geometrically nonlinear analysis approach, which is based on the Reissner-Mindlin-Von K´arm´an type shell facet model, has been implemented into the Elmer FE solver. Altair ESAComp software runs the Elmer Solver in the background. A post-processing capability, which enables the prediction of the delamination onset from the FEA output, has been implemented into the AltairESAComp software. A Virtual Crack Closure Technique (VCCT) speciﬁcally developed for shell elements deﬁning the Strain Energy Release Rate (SERR) related to the diﬀerent delamination modes at the crack front is used. The onset of delamination is predicted using the relevant delamination criteria that utilize the SERR data and material allowables in the form of fracture toughness. The modeling methodology is presented for laminates including initial through-the-width delamination. Examples include delamination in the solid laminate and debonding of the skin laminate in the sandwich structure. Rather coarse FE mesh has proved to yield good results when compared to typical approaches that utilize the standard VCCT or Cohesive Zone Elements.

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