Optimal design and testing of laminated specimens to evaluate competing composite failure criteria

Optimization methods are used to find areas of maximum disagreement between the failure criteria of Tsai and Hart-Smith. The Tsai criterion is quadratic in the stresses and employs a selective and progressive ply-by-ply degradation scheme to predict ultimate load. Hart-Smith’s criterion is based on a fiber shear failure of the fibers and also predicts ultimate load. Both compression-compression and tension-shear combinations are identified as areas of large difference in predicted failure loads. Graphite-epoxy specimens are designed to maximize the difference in the failure loads computed from the two criteria under uniaxial tension. Both on-axis and ten-degree off-axis specimens are designed and tested. The laminates that maximize the difference in these criteria exploit the manner in which they treat the effect of in-plane shear on the failure prediction. Test results indicate little difference in the failure prediction for the on-axis test. However, the off-axis tests show that the Tsai criterion predicts failure much closer to the test results.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Aerospace Engineering

Department dc:contributor.department

Aerospace Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1993

Author dc:creator

• Wamelen, Arend Andries van

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-08042009-040517

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/44176