Development of a physics-based theory for mixed mode I/II delamination onset in orthotropic laminates

Development of a physics-based theory for mixed mode I/II delamination onset in orthotropic laminates

Daneshjoo, Z. (TU Delft Structural Integrity & Composites; Iran University of Science and Technology)
Amaral, L. (TU Delft Structural Integrity & Composites)
Alderliesten, R.C. (TU Delft Structural Integrity & Composites)
Shokrieh, M. M. (Iran University of Science and Technology)
Fakoor, M. (University of Tehran)

2019-10-01

This paper demonstrates how the critical strain energy density in the delamination tip vicinity may be used to explain the physics of delamination growth under mixed mode I/II. A theory previously proposed to physically relate mode I and mode II delamination growth is further extended towards describing the onset of mixed mode I/II delamination. Subsequently, data from the literature is used to demonstrate that this new concept of the critical strain energy density approach indeed explains, based on the physics of the problem, the strain energy release rate level at which crack onset occurs. This critical strain energy density for the onset of delamination appears to be independent of the opening mode. This means that, in order to characterize the fracture behaviour of a laminate, fracture tests at only one loading mode are necessary. Because the load level at which the physical delamination onset occurs at the microscopic level is much lower than the traditional engineering definition of macroscopic onset, further work must reveal the relationship between the macroscopically visible delamination onset, and the microscopic onset.

Delamination
Laminated composite
Mixed mode I/II loading
Strain energy density

http://resolver.tudelft.nl/uuid:609153ac-6a97-458e-93b3-e8b119128d5c

https://doi.org/10.1016/j.tafmec.2019.102303

0167-8442

Theoretical and Applied Fracture Mechanics, 103

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

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journal article

© 2019 Z. Daneshjoo, L. Amaral, R.C. Alderliesten, M. M. Shokrieh, M. Fakoor