Engineering topics

Armanios, E. A.

Publications and source records attributed to Armanios, E. A..

3 records

NASA NTRS1989

Fracture analysis of local delaminations in laminated composites

A shear deformation model was developed to analyze local delaminations growing from transverse cracks in 90 degree plies located around the mid plane of symmetric laminates. The predictions of the model agree reasonably with experimental data from T300/934 graphite epoxy laminates. The predicted behavior is such that, in combination with an edge delamination model, the critical loads can be predicted accurately in the range of n from .5 to 8.

Armanios, E. A.↗

NASA NTRS1986

Sublaminate analysis of interlaminar fracture in composites

A simple analysis method based upon a transverse shear deformation theory and a sublaminate approach is utilized to analyze a mixed-mode edge delamination specimen. The analysis provides closed form expressions for the interlaminar shear stresses ahead of the crack, the total energy release rate, and the energy release rate components. The parameters controlling the behavior are identified. The effect of specimen stacking sequence and delamination interface on the strain energy release rate components is investigated. Results are compared with a finite element simulation for reference. The simple nature of the method makes it suitable for preliminary design analyses which require a large number of configurations to be evaluated quickly and economically.

Armanios, E. A.↗

NASA NTRS1986

Interlaminar analysis of laminated composites using a sublaminate approach

A simple analysis method based upon a transverse shear deformation theory and a sublaminate approach is utilized to analyze a Mixed-Mode edge delamination specimen. The analysis provides a closed form distribution of the interlaminar shear stresses ahead of the crack, and the parameters controlling the behavior are identified. The effect of specimen stacking sequence and delamination interface on the strain energy release rate components is investigated. Results are compared with a finite element simulation for reference. The simple nature of the method makes it suitable for preliminary design analyses which require a large number of configurations to be evaluated quickly and economically.

Armanios, E. A.↗