PSI - Issue 42

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ScienceDirect

Procedia Structural Integrity 42 (2022) 1537–1544 Structural Integrity Procedia 00 (2019) 000–000 Structural Integrity Procedia 0 (20 9) 000–000

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© 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 Abstract Experimental testing of concrete samples is of crucial importance when obtaining material properties of existing concrete struc tures or verifying proper design of a new concrete mixture. The uniaxial compression test of concrete samples enables engineers to acquire compressive strength of the material, which is needed in structural design. One of the factors potentially influencing the outcome of the tests is the friction on the interface between the loading platens and the specimen. Depending on the specimen’s geometry, the phenomenon may alter the inner failure mechanism, resulting in artificial increase of the specimen’s strength. The contribution illustrates and describes the e ff ect of friction in uniaxial compressive testing of concrete cylindrical drill-core specimens of various slenderness ratios. Using calibrated discrete mesoscale model, di ff erent friction scenarios are simulated and compared to experimental results. © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativec mmons.org / licenses / by-nc-nd / 4.0 / ) er-review under responsibility of 23 European Conference on Fracture – ECF23 . Keywords: Concrete; Fracture; Uniaxial compression; Friction; Discrete model; Failure Abstract Experimental testing of concrete samples is of crucial importance when obtaining material properties of existing concrete struc tures or verifying proper design of a new concrete mixture. The uniaxial compression test of concrete samples enables engineers to acquire compressive strength of the material, which is needed in structural design. One of the factors potentially influencing the outcome of the tests is the friction on the interface between the loading platens and the specimen. Depending on the specimen’s geometry, the phenomenon may alter the inner failure mechanism, resulting in artificial increase of the specimen’s strength. The contribution illustrates and describes the e ff ect of friction in uniaxial compressive testing of concrete cylindrical drill-core specimens of various slenderness ratios. Using calibrated discrete mesoscale model, di ff erent friction scenarios are simulated and compared to experimental results. © 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: Concrete; Fracture; Uniaxial compression; Friction; Discrete model; Failure 23 European Conference on Fracture – ECF23 Friction e ff ects in uniaxial compression of concrete cylinders Monika Stˇredulova´ a, ∗ , Dominik Lisztwan b , Jan Elia´sˇ a a Institute of Structural Mechanics, Faculty of Civil Engineering, Brno University of Technology, Veverˇ´ı 331 / 95, Brno 60200, Czechia b Institute of Building Testing, Faculty of Civil Engineering, Brno University of Technology, Veverˇ´ı 331 / 95, Brno 60200, Czechia 23 European Conference on Fracture – ECF23 Friction e ff ects in uniaxial compression of concrete cylinders Monika Stˇredulova´ a, ∗ , Dominik Lisztwan b , Jan Elia´sˇ a a Institute of Structural Mechanics, Faculty of Civil Engineering, Brno University of Technology, Veverˇ´ı 331 / 95, Brno 60200, Czechia b Institute of Building Testing, Faculty of Civil Engineering, Brno University of Technology, Veverˇ´ı 331 / 95, Brno 60200, Czechia Experimental testing of concrete has an essential role in a design process. It allows engineers to directly measure or identify material characteristics of a concrete mix, either from an existing structure or as a newly designed recipe. Among di ff erent standardized testing procedures, the uniaxial compression test of concrete holds a prominent position because of (i) its straightforward execution and deduction of desired parameters and (ii) the importance of the com pressive strength in design (Neville, 2012). Cubes or cylinders of standardized dimensions are commonly used for such tests. According to Neville (2012), preference is given to one or the other in some countries. The European standard for testing of hardened concrete (Eurocode 2, 2004) allows the use of both. The code considers standardized cubes of 150 mm edge length and cylinder (or drill-core specimen) of 150 mm diameter and 300 mm height, but other dimensions are also possible. The code doesn’t specify the smallest possible size of the cube; but in the case of the cylinder / drill-core specimen, the smallest Experimental testing of concrete has an essential role in a design process. It allows engineers to directly measure or identify material characteristics of a concrete mix, either from an existing structure or as a newly designed recipe. Among di ff erent standardized testing procedures, the uniaxial compression test of concrete holds a prominent position because of (i) its straightforward execution and deduction of desired parameters and (ii) the importance of the com pressive strength in design (Neville, 2012). Cubes or cylinders of standardized dimensions are commonly used for such tests. According to Neville (2012), preference is given to one or the other in some countries. The European standard for testing of hardened concrete (Eurocode 2, 2004) allows the use of both. The code considers standardized cubes of 150 mm edge length and cylinder (or drill-core specimen) of 150 mm diameter and 300 mm height, but other dimensions are also possible. The code doesn’t specify the smallest possible size of the cube; but in the case of the cylinder / drill-core specimen, the smallest 1. Introduction 1. Introduction

∗ Corresponding author. Tel.: + 420-541-147-131 E-mail address: stredulova.m@fce.vutbr.cz ∗ Corresponding author. Tel.: + 420-541-147-131 E-mail address: stredulova.m@fce.vutbr.cz

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.2022.12.194 2210-7843 © 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 . 2210-7843 © 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 .