PSI - Issue 28

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

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 28 (2020) 1883–1891

© 2020 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 European Structural Integrity Society (ESIS) ExCo Abstract Cement mixtures are a key element in the manufacture of concrete as the strength and durability of concrete structures largely depend on the properties of cement. The use of modern methods for strain measurements allows to obtain important information about the strain behavior within the material under study. The paper discusses the possibility of using fiber-optic sensors based on Bragg gratings embedded in cement mixture samples with different geometric shapes for recording the history and evolution of process-induced strains during the formation of samples. The paper presents a laboratory method for embedding fiber-optic sensors without additional protective coating layers except for the polyimide coating into a cement mixture. Fiber-optic sensors were embedded along the length of the samples, which made it possible to obtain information about the strain distribution. An experimental stand was designed and created to evaluate the shrinkage process and the internal temperature of the test samples made of cement mixture, as well as the temperature and humidity of the environment. The dependence of strain on the sample length is presented. Despite some limitations, the proposed laboratory technique for obtaining data about process-induced strains in cement mixtures can be used to construct and validate models of the mechanical behavior of concrete. © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. e 1st Virtual European Conference on Fracture Registration of evolution of process-induced strains in cement mixtures by embedded fiber Bragg grating sensors Kosheleva N.A. a *, Serovaev G.S. a , Gusev G.N. a a Institute of Continuous Media Mechanics UB RAS, 1, Akademika Koroleva Str.,Perm, 614013, Russia

Keywords: process-induced strains; cement mixture; embedded fiber-optic sensors; Bragg grating

1. Introduction The strength and durability of important engineering structures is largely determined by the mechanical state of structural elements made of concrete. The need for monitoring the state of the structures increases sharply because of

* Corresponding author. Tel.: +7(342)-237-83-08. E-mail address: nataly.kosheleva@gmail.com

2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers.

2452-3216 © 2020 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 European Structural Integrity Society (ESIS) ExCo 10.1016/j.prostr.2020.11.011