PSI - Issue 42

Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ^ĐŝĞŶĐĞ ŝƌĞĐƚ Structural Integrity Procedia 00 (2019) 000 – 000 ^ĐŝĞŶĐĞ ŝƌĞĐƚ

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Procedia Structural Integrity 42 (2022) 1000–1007

23 European Conference on Fracture - ECF23 Numerical study of specimen with steel inclusion: Influence of interfacial transition zone Michal Vyhlídal a, *, Jan Klusák b a Brno University of Technology, Faculty of Civil Engineering, Veveří 331/95, 602 00 Brno, Czech Republic b Czech Academy of Sciences, Institute of Physics of Materials, Žižkova 22, 616 00 Brno, Czech Republic 23 European Conference on Fracture - ECF23 Numerical study of specimen with steel inclusion: Influence of interfacial transition zone Michal Vyhlídal a, *, Jan Klusák b a Brno University of Technology, Faculty of Civil Engineering, Veveří 331/95, 602 00 Brno, Czech Republic b Czech Academy of Sciences, Institute of Physics of Materials, Žižkova 22, 616 00 Brno, Czech Republic

© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the 23 European Conference on Fracture – ECF23 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23 Keywords: : Steel inclusion, fracture test, numerical simulation, crack propagation path, the criterion of average tangential stress. Abstract In this paper, the influence of the interfacial transition zone (ITZ) betw en steel inclusion a d fine- rained cement-based co posite on fr cture behaviou investigated. Sp cimens the nominal dimensions 40 × 40 × 160 m w th the steel inclusion of the prismatic shape with nominal dimensions 8 × 8 × 40 mm were provided with an initial cen ral edge notch wit a depth 12 mm. Th ai of thi p per is o analyse the behaviour of such specimen by m ans of numerical modelling by finit element method (Ansys s ftware). A simplified 2D mod l (pl ne strain) based on th fracture est confi ura ion was created. T crack propagation assessment was based on the criterion of the average value of tang ntial stress θθ calculate over certain distance d in dependence on the polar coordinate θ . It is a umed that the crack is initiated when th averag stress ̅ θθ ( 0 ) reaches its critical value ̅ θθ,c ( 0 ) , which depends on the fracture oughnes Ic of the m terial nd on the distance d . From the detailed numeric l analysis of the described fractur test, we conc uded hat the crack propagation path depends strongly on the fracture properties of ITZ. The central inclusion works as an obstacle to crack propagation only in the initial stage of failure. The mechanical fracture parameters of the ITZ strongly influence the overall fracture behavior of test specimens. © 2020 The Autho s. Publ shed by Elsevier B.V. This is an open ac es article nd r the CC BY-NC-ND license (http://creativecommons.org/licenses/by- c-nd/4.0/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23 Keywords: : Steel inclusion, fracture test, numerical simulation, crack propagation path, the criterion of average tangential stress. Abstract In this paper, the influence of the interfacial transition zone (ITZ) between steel inclusion and fine-grained cement-based composite on fracture behaviour is investigated. Specimens of the nominal dimensions 40 × 40 × 160 mm with the steel inclusion of the prismatic shape with nominal dimensions 8 × 8 × 40 mm were provided with an initial central edge notch with a depth 12 mm. The aim of this paper is to analyse the behaviour of such specimen by means of numerical modelling by finite element method (Ansys software). A simplified 2D model (plane strain) based on the fracture test configuration was created. The crack propagation assessment was based on the criterion of the average value of tangential stress θθ calculated over certain distance d in dependence on the polar coordinate θ . It is assumed that the crack is initiated when the average stress ̅ θθ ( 0 ) reaches its critical value ̅ θθ,c ( 0 ) , which depends on the fracture toughness Ic of the material and on the distance d . From the detailed numerical analysis of the described fracture test, we concluded that the crack propagation path depends strongly on the fracture properties of ITZ. The central inclusion works as an obstacle to crack propagation only in the initial stage of failure. The mechanical fracture parameters of the ITZ strongly influence the overall fracture behavior of test specimens.

* Corresponding author. E-mail address: Michal.Vyhlidal@vutbr.cz * Corresponding author. E mail address: Michal.Vyhlidal@vutbr.cz

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23 2452 3216 © 2020 Th Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23

2452-3216 © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the 23 European Conference on Fracture – ECF23 10.1016/j.prostr.2022.12.126