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Aerospace Engineering

Aerospace Engineering

1999

Articles 1 - 3 of 3

Full-Text Articles in Engineering

Mixed Mode Stable Crack Extensions Through Stiffened Specimens, Abdel-Hamid I. Mourad, Eltahry Elghandour, Faysal A. Kolkailah May 1999

Mixed Mode Stable Crack Extensions Through Stiffened Specimens, Abdel-Hamid I. Mourad, Eltahry Elghandour, Faysal A. Kolkailah

Aerospace Engineering

This study presents an experimental investigation of fracture mechanics for isotropic material, aluminum alloy D16AT. The problem of stable crack growth (SCG) has been addressed in this paper. Experimental results are presented for symmetrically stiffened and unstiffened three point bend specimens subjected to different modes, mode I and mixed mode. The stiffeners are doubly bonded to the fatigue pre-cracked specimens parallel to the length at a certain distance behind the crack tip using an adhesive Redux 410 NA. Results concerning load displacement variation, growth of plastic zones, instantaneous crack edge profiles, and tunneling are presented. There is evidence that the …


Sensors Location Effect On The Dynamic Behaviour Of The Composite Structure With Flaw Detection, Eltahry Elghandour, Faysal Kolkailah, Abdel- Hamid I. Mourad May 1999

Sensors Location Effect On The Dynamic Behaviour Of The Composite Structure With Flaw Detection, Eltahry Elghandour, Faysal Kolkailah, Abdel- Hamid I. Mourad

Aerospace Engineering

In this paper presents an experimental and numerical investigation ofthe natural frequency of composite material cantilever plates. The stacking sequence of tbe composite plate is Quasi-isotropic laminated plate is [2(0j/±45°/2(90°)]" The plate was subjected to incremental cuts and tests to determine changes in new modal properties. The study included white noise and sinusoidal dynamic testing techniques and a virtual instrument dynamic analyzer. In this study also, determining the resonant frequencies of the undamaged and damaged plate, and evaluating the capabilities of piezoelectric ceramics (PZT's) for fault detection based on their sensitivity and accuracy changes in modal parameters. Numerical results are …


Location Effects Of Passive Damping Material In Cross-Ply Laminates On Natural Frequency And Mode Shape, E. I. Elghandour, F. A. Kolkailah Jan 1999

Location Effects Of Passive Damping Material In Cross-Ply Laminates On Natural Frequency And Mode Shape, E. I. Elghandour, F. A. Kolkailah

Aerospace Engineering

This study presents an experimental investigation of the free vibration of cantilevered composite laminated plates with embedded passive damping material at different stages. A total of five composite laminated plates are considered. The lay-up sequences for the five composite laminated plates with and without two embedded layers of passive damping material are [90°/0°/90°/0°]s, [90°/0°/90°/0°/d]s, [90°/0°/90°/d/0°]s, [90°/0°/d/90°/0°]s, and [90°/d/0°/90°/0°]s. The passive damping material employed is a 3M material, SJ-2015 ISD 112, with peak damping properties in the ambient temperature range of 32°F to 140°F. The composite material used is a carbon …