Issue 39

S. Seitl et alii, Frattura ed Integrità Strutturale, 39 (2017) 118-128; DOI: 10.3221/IGF-ESIS.39.13 118 Focussed on Modelling in Mechanics Modified compact tension specimen for experiments on cement based materials: comparison of calibration curves from 2D and 3D numerical solutions S. Seitl, V. Viszlay Brno University of Technology, Faculty of Civil Engineering, Veveří 331/95, Brno 602 00, Czech Republic Seitl.s@fce.vutbr.cz , http://orcid.org/0000-0002-4953-4324 , viszlay.v@fce.vutbr.cz A BSTRACT . The evaluation of fracture mechanics parameters of materials has become very important part of considering the condition of older constructions as well as properties of newly developed materials. This contribution focuses on a numerical simulation and a calculation of fracture mechanical properties of modified compact tension test configuration. It is possible to prepare the specimens used for this test very easily from a drilled core or from specimens used for cylindrical compression test. The focus of contribution is to compare selected outputs from numerical solution of 2D (plane strain conditions) with 3D models. Particularly, the determination of the influence of 2D and 3D model on the calibration curves for selected fracture mechanics parameters is of interest. Finite element software ANSYS was used for the numerical analysis. K EYWORDS . Stress Intensity Factor; COD; CMOD; Biaxiality Factor; Modified Compact Tension Test; Fracture Mechanics of Concrete. Citation: Seitl, S., Viszlay, V., Modified compact tension specimen for experiments on cement based materials: comparison of calibration curves from 2D and 3D numerical solutions, Frattura ed Integrità Strutturale, 39 (2017) 118-128. Received: 17.07.2016 Accepted: 22.09.2016 Published: 01.01.2017 Copyright: © 2017 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. I NTRODUCTION ompact tension (CT) tests have been widely and successfully applied for measuring the fracture properties of several materials, such as metals (ASTM Standard E-399 [3]), or even composite materials with limited orthotropy [1]. Note that for test of fracture properties is not prepared norm only recommendation RILEM for three point bending test [17], RILEM for bending test for concrete with fibers [16, 18] and as a standard test the wedge splitting test is used (cube or cylindrical [12, 14, 19, 20]). The compact tension fracture toughness test (CT test [11, 22]) is essentially performed by applying equal and opposite forces through two holes previously made in the specimen, to propagate an initial crack. However, its applicability in concrete is characterized by some disadvantages, such as drilling the holes necessary to apply C