Effect of z-Pins on Fracture in Composite Cocured Double Cantilever Beams
Publication: Journal of Aerospace Engineering
Volume 18, Issue 1
Abstract
The paper illustrates a new approach to the evaluation of the effect of z-pins on deformations and the strain energy release rate in composite double cantilever beams (DCB) subject to a standard fracture toughness test. The effect of z-pins is modeled by an elastic foundation, based on previously published work. The approach to the solution is based on a separate analysis of the intact and delaminated parts of DCB. The rotational stiffness of the intact part is obtained from the Rayleigh-Ritz solution for this part subjected to a force couple, rather than modeling the rotational restraint by introducing an elastic foundation, as has been done in the previous studies. Subsequently, the deformation of the delaminated part of DCB is analyzed exactly by solving the equation of equilibrium with the appropriate boundary conditions. Based on this solution, the compliance, the rate of change of compliance, and the strain energy of the specimen can be evaluated. The results illustrate the beneficial effect of z-pins on the resistance of DCB to delamination cracking.
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Acknowledgment
This research was supported by the Air Force Office for Scientific Research, Contract No. F33615-98-D-3210.
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Information & Authors
Information
Published In
Journal of Aerospace Engineering
Volume 18 • Issue 1 • January 2005
Pages: 51 - 59
Copyright
© 2004 ASCE.
History
Received: Sep 2, 2003
Accepted: Feb 11, 2004
Published online: Jan 1, 2005
Published in print: Jan 2005
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