Issue 35

T. Holušová et alii, Frattura ed Integrità Strutturale, 35 (2016) 242-249; DOI: 10.3221/IGF-ESIS.35.28 242 Focussed on Crack Paths A numerical study of two different specimen fixtures for the modified compact tension test – their influence on concrete fracture parameters T. Holušová S. Seitl (http://orcid.org/0000-0002-4953-4324 ) Institute of Structural Mechanics, Faculty of Civil Engineering, Brno University of Technology Institute of Physics of Materials, Academy of Sciences of the Czech Republic holusova.t@fce.vutbr.cz ; seitl@ipm.cz H. Cifuentes (http://orcid.org/0000-0001-6302-418X ) Dept. of Continuum Mechanics and Structural Analysis, University of Seville bulte@us.es A. Fernández-Canteli (http://orcid.org/0000-0001-8071-9223 ) Dept. Of Construction and Manufacturing Engineering, University of Oviedo afc@uniovi.es A BSTRACT . The modified compact tension test (MCT) may represent a new test configuration for the performance of static and other kinds of fatigue tests on concrete-like materials. Core drilling can be employed to obtain specimens which are cylindrical in shape and have a standard diameter of 150 mm, this being appropriate for the determination of the residual life of structures. This contribution focuses on the evaluation of MCT specimen fracture behavior during static tests. Cracks evolution are simulated numerically using ATENA finite element (FE) software, while the results are represented as L-COD diagrams, i.e. load vs. crack opening displacement measured on the loading axis. After numerical calculations, the results for two different fixtures are compared and the advantages or drawbacks for each solution are discussed. K EYWORDS . Modified Compact Tension Test; Fracture Parameters; Cementitious Composites; FEM. I NTRODUCTION AND MOTIVATION nowledge regarding the fracture mechanics behavior (parameters) of the most common building material, concrete, plays a significant role in the determination of the residual life of previously built constructions. This is especially true for concrete used in buildings after several years of aging. Drill cores commonly used for the determination of concrete age, can be extracted from real (existing) structures. Cylindrical specimens with the selected thickness can be cut from the drill cores. This kind of specimen can be used for the modified compact tension test (MCT), whose numerical evaluation is useful for the determination of relevant fracture-mechanics parameters of concrete K