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Analisys and Advanced Materials for Structural DesignAnàlisis i Materials Avançats pel Disseny Estructur al

Continuum damage models forcomposite materials

From material to structural design

Pere Maimí

University of Girona

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Strategy of Composite Structural design

INDUSTRY STRATEGY : BUILDING BLOCK APPROACHINDUSTRY STRATEGY : BUILDING BLOCK APPROACH

NUMERICAL TOOLS NEED FURTHER IMPROVEMENTS TO REDUCE COST OF LABOTATORY TESTING IN MATERIAL AND STRUCTURAL DE SIGN

Conceptual design

LaboratoryTesting

Virtual Mechanical

Testing

ExperienceDatabase

Final design

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• Models can be implemented in a commercialfinite element codes, allowing to solve structureswith complex geometries.

• Thermodynamics of irreversible processes offersa rigorous framework.

• Capability of treat couplet problems. Damage, plasticity, thermal dilatation …

• Models are able to detect the onset (stress criteria) and the evolution (Energy dissipation) ofinternal variables.

Why Continuum damage mechanics?

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IDM

TIDM

0

090

0

Compountsproperties:

-Elastic-Strength-Fracture energy

Compositeproperties:

-Elastic-Strength-Fracture energy

Composite design strategy: building block approach in VMT

Laminateproperties:

-Elastic-Matrix cracking-Strength-Fracture energy

Structural response

-Resistence-Damage tolerance-Global ductility

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• Damage model for isotropic materials (IDM)• Element SOLID 3D ABAQUS

• Damage model for transversely isotropicmaterials (TIDM)

• Element SOLID 3D ABAQUS

• Damage model for composite laminates(mesomodels)

• Element thin shell ABAQUS

Continuum damage models developed

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Laminate properties: (TIDM), Matrix cracking, TENSION

0900

0900

0900

0900

0900

0900

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Laminate properties: (TIDM), Matrix cracking, COMPRESSION

90º

0º

0º

DEFORMED X25

MATRIX CRACKS UNDER COMPRESSIVE

LOADS

DELAMINATIONS

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Laminate properties: (TIDM), Matrix cracking, COMPRESSION

MATRIX CRACKSDELAMINATIONS

0º

90º

0ºMaximum compressive principal strain

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Damage model for laminated structures (mesomodel)

AS4/3501-6[45/-45/02/90/02/-45/45]

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Damage model for laminated structures (mesomodel)

Fiber damage onset in 0º ply

F

∝∝∝∝ displacement

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http://amade.udg.es