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Licensed Unlicensed Requires Authentication Published by De Gruyter July 26, 2017

Determination of mode I and mode II fracture toughness of walnut and cherry in TR and RT crack propagation system by the Arcan test

Koji Murata, Erik Valentine Bachtiar and Peter Niemz
From the journal Holzforschung

Abstract

Two specimen types, each from walnut and cherry wood, were prepared for tangential-radial (TR) and radial-tangential (RT) crack propagation systems at 65% of RH and 20°C before mode I and mode II fracture toughness was determined through Arcan tests. It was found that fracture toughness in mode I is in agreement with literature data. In the mode II test, however, the crack propagated in the direction normal to the shear plane and not parallel to it. The release rate of strain energy in terms of the opening failure in mode II was lower than that in mode I. It can be concluded that it is difficult to determine the fracture toughness of RT or TR propagation in hardwood specimens in mode II.

Acknowledgments

The authors would like to acknowledge the financial support of the Swiss National Science Foundation (SNF) project no. 147672 and Kyoto University Young Scholars Overseas Visit Program (The John Mung Program).

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Received: 2017-4-21
Accepted: 2017-6-19
Published Online: 2017-7-26
Published in Print: 2017-11-27

©2017 Walter de Gruyter GmbH, Berlin/Boston