PSI - Issue 28

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

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 28 (2020) 2291–2296

© 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 The research was made to study the effect of low amplitude loads on the fatigue life of CFRP samples with impact damage in a cyclogram of irregular loading. The evaluation of the applicability of the linear summation hypothesis of damage (Palmgren’s Miner’s rule) at this level of loading was also carried out. The results have shown that in some cases correction factors need to be introduced. © 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 Keywords: Low amplitude loads, CFRP, impact damage, irregular loading. 1. Introduction For an experimental evaluation of fatigue life of aircraft structures from CFRP, loading spectra are used, which are formed on the basis of data on the typical flight of an aircraft. Such spectra contain a large number of loading cycles of low amplitude. In order to optimize and at the same time preserve “authenticity”, it is necessary to evaluate how this type of loading affects fatigue life and what damage such cycles introduce. For this purpose, it was made the research of the effect of low amplitude loads on the fatigue life of CFRP specimens with impact damage in a cyclogram of irregular loading. Also, it was carried out the verification of an applicability of the method of analytical evaluation of fatigue life, which was described in the article [1]. 1st Virtual European Conference on Fracture Investigation of the influence of low amplitude loads on the fatigue life of CFRP specimens with impact damage under irregular loading A.A. Lukyanchuk*, A.V. Pankov, A.G. Kalinin, V.V. Konovalov, V.G. Lukyanchuk Central aerohydraudynamic institute n.a. Prof. N.E. Zhukovsky (TsAGI),Russia Abstract The research was made to study the effect of low amplitude loads on the fatigue life of CFRP samples with impact damage in a cyclogr m of irregular loading. The evalua ion of the applicability of the linear sum ation hypothesis of d mage (Palmgren’s Miner’s rule) t this lev l of o di g was also carried out. T result have sh wn tha in some c s s correctio factors need to be introduced. © 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 u der responsibility of e European Structural Integrity So iety (ESIS) ExCo K ywords: Low amplitude loads, CFRP, impact dam ge, irregular loading. 1. Introduction For an experimental evaluation of fatigue life of aircraft structures from CFRP, loading spectra are used, which are formed on the basis of dat on the typical flight n aircraft. S ch spectra contain lar e number of loading ycles of low amplitude. In or er t optimize nd at the s me time preserve “authenticity”, it is necessa y to evaluate how this type of loading affects fatigue life and w at da age such cycl s introduce. For his purpose, it was made the research of the effect o low amplitude lo ds on the f tigue life of CFRP specimens with impact damage in cyclogram of irregular loading. Als , it was carried out the v rification of an applicability of the method of an lyt cal eva uation fati e life, which was described in the ar icle [1]. 1st Virtual European Conference on Fracture Investigation of the influence of low amplitude loads on the fatigue life of CFRP specimens with impact damage under irregular loading A.A. Lukyanchuk*, A.V. Pankov, A.G. Kalinin, V.V. Konovalov, V.G. Lukyanchuk Central aerohydraudynamic institute n.a. Prof. N.E. Zhukovsky (TsAGI),Russia

* Corresponding author. E-mail address: andrey.lukyanchuk@tsagi.ru * Corresponding author. E-mail address: andrey.lukyanchuk@tsagi.ru

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 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 u der responsibility of t European Structural Integrity So i ty (ESIS) ExCo

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.2020.11.075