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Size effect and quasi-brittle fracture: the role of FPZ

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Abstract

Fracture process zone (FPZ), or the crack-tip damage zone created by crack-bridging and micro-cracking activities, in a specimen of a concrete-like material is comparable to the crack size and un-cracked ligament, so fracture is typically quasi-brittle. Increasing or decreasing the specimen size, quasi-brittle fracture transition occurs towards the toughness-controlled or strength-controlled fracture, which is known as size effect (SE). In this study it is shown that the “size-dependent” quasi-brittle fracture transition is actually due to the interaction of FPZ with the nearest structure boundary rather than the size variation, and the widely-accepted SE for geometrically-similar specimens of different sizes is only a special case of quasi-brittle fracture controlled by the FPZ/boundary interaction. Relevant SE relations are critically reviewed and explained by emphasizing the key SE mechanism, FPZ/boundary interaction.

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Authors and Affiliations

  1. School of Mechanical Engineering, University of Western Australia, Perth, WA, 6009, Australia

    Xiaozhi Hu

  2. PELM & Department of Infrastructures, Faculty of Science, Engineering & Health, CQ-University, Gladstone, QLD, 4680, Australia

    Kai Duan

Authors
  1. Xiaozhi Hu
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  2. Kai Duan
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Correspondence to Xiaozhi Hu.

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Hu, X., Duan, K. Size effect and quasi-brittle fracture: the role of FPZ. Int J Fract 154, 3–14 (2008). https://doi.org/10.1007/s10704-008-9290-7

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  • DOI: https://doi.org/10.1007/s10704-008-9290-7

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