cahtНаучный вестник МГТУ ГАCivil Aviation High Technologies2079-06192542-0119Moscow State Technical University of Civil Aviation (MSTU CA)caht-318Research ArticleСтатьиИспользование линейных моделей в расчетах длительности роста трещин при случайных нагрузкахThe linear model using in crack growth simulation under variable-amplitude loadingНиконовВ. В.NikonovV. V.noemail@neicon.ruШапкинВ. С.ShapkinV. S.noemail@neicon.ruMSTU CARussian FederationSSRI CARussian Federation20140711201602081321Copyright © Никонов В.В., Шапкин В.С., 20162016Никонов В.В., Шапкин В.С.Nikonov V.V., Shapkin V.S.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://avia.mstuca.ru/jour/article/view/318

В работе приводятся экспериментальные и теоретические результаты исследований в области оценок длительности роста трещин в условиях воздействия нерегулярных нагрузок, имитирующих эксплуатационные. Показана возможность применения моделей типа Пэриса-Эрдогана для расчетов периода живучести тонкостенных элементов авиаконструкций. Установлена аналогия в расчетах долговечности и расчетах живучести. Вводится понятие меры повреждений для оценки возможности применения линейной модели накопления повреждений в расчетах длительности роста трещин. Теоретические положения сопоставляются с результатами экспериментальных исследований трещиностойкости плоских образцов-пластин из сплавов Д16АТ (аналог 2024-Т3) и В95АТВ (аналог 7075-Т6). Нагружение в эксперименте представляло собой стационарные гауссовские процессы.

The paper shows the possibility of using Paris-Erdogan equation for simulation fatigue crack growth under random loading. The considered equation has introduced the effective stress intensity factor range. The introduced methodology for crack growth simulation is based on the concept of a “basic” random loading. The discussed methodology included consideration of overloads influence on the fatigue crack growth. The theoretical model is based on the experimental researches of fatigue crack growth under random loading that have been realized during specimens fatigue tests of two Al-based alloys (D16chАТ - the same as 2024-T3, and В95АТВ - 7075-T6). In the tests the specimens of a center cracked panel were used. In all cases the random loading has been considered as Gaussian processes of cyclic loading with introduced and discussed parameters of investigated processes. As a result of investigations the model for estimation crack growth period in the different random of irregular cyclic loads was introduced.

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The authors declare that there are no conflicts of interest present.