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Accession Number ADA591210
Title Novel Method for Dynamic Short-Beam Shear Testing of 3D Woven Composites.
Publication Date Aug 2011
Media Count 14p
Personal Author B. V. Sankar C. F. Yen G. Subhash M. C. Song T. R. Walter
Abstract A new test method for performing dynamic short-beam shear tests using a momentum trapped Hopkinson pressure bar is proposed. Angle-interlock 3D woven composite specimens were tested under quasi-static and dynamic loading conditions to determine the effect of loading rate on damage evolution. The equilibrium condition in the composite specimen under dynamic loads was verified using finite element analysis of the experiment. A high speed camera was used to capture delamination initiation and propagation during both quasi- static and dynamic experiments. Analysis of the load-deflection curves and the high speed images revealed a good correlation between the modes of damage initiation and propagation with the features in the loading response. The apparent inter-laminar shear strength and the bending stiffness increased with rate of loading. While the damage was observed to propagate at a relative steady rate during quasi-static loading, the high rate of energy input during dynamic loading resulted in a rapid propagation of damage and a subsequent loss of stiffness in the composite as noted in the load-deflection curve.
Keywords Bending
Composite materials
Dynamic loads
Finite element analysis
Hopkinson pressure bars
Inter-laminar shear strength
Sbs(Short-beam shear testing)
Shear strength
Strain rate
Test and evaluation
Three dimensional
Woven composites

Source Agency Non Paid ADAS
NTIS Subject Category 71F - Composite Materials
94K - Laboratory & Test Facility Design & Operation
46E - Structural Mechanics
Corporate Author Florida Univ., Gainesville. Dept. of Mechanical and Aerospace Engineering.
Document Type Journal article
Title Note Journal article.
NTIS Issue Number 1411
Contract Number W911NF-08-1-0120

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