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Does the shear-lag model apply to random fiber networks?

Published online by Cambridge University Press:  31 January 2011

V. I. Räisänen ,
M. J. Alava ,
K. J. Niskanen  and
R. M. Nieminen
V. I. Räisänen
Affiliation:
CSC–Center for Scientific Computing, P.O. Box 405, FIN-02101 Espoo, Finland
M. J. Alava
Affiliation:
Helsinki University of Technology, Laboratory of Physics, FIN-02150 Espoo, Finland
K. J. Niskanen
Affiliation:
KCL Paper Science Centre, P.O. Box 70, FIN-02151 Espoo, Finland
R. M. Nieminen
Affiliation:
CSC–Center for Scientific Computing, P.O. Box 405, FIN-02101 Espoo, Finland and Helsinki University of Technology, Laboratory of Physics, FIN-02150 Espoo, Finland
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Abstract

The shear-lag type model due to Cox (Br. J. Appl. Phys. 3, 72 (1952) is widely used to calculate the deformation properties of fibrous materials such as short fiber composites and random fiber networks. We compare the shear-lag stress transfer mechanism with numerical simulations at small, linearly elastic strains and conclude that the model does not apply to random fiber networks. Most of the axial stress is transferred directly from fiber to fiber rather than through intermediate shear-loaded segments as assumed in the Cox model. The implications for the elastic modulus and strength of random fiber networks are discussed.

Type
Articles
Information
Journal of Materials Research , Volume 12 , Issue 10 , October 1997 , pp. 2725 - 2732
Copyright
Copyright © Materials Research Society 1997

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References

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