Theoretical interpretation of size effect in fatigue

• Autorzy: Carpinteri, A. , Landini, A. , Spagnoli, A.
• Konferencja: Summer School Of Fracture Mechanics. Current Research On Fatigue And Fracture/sympozjum (VII ; 18-22.06.2001 ; Opole - Pokrzywna, Poland)
• Języki publikacji: EN

Abstrakty

EN

As is well-known, the fatigue strength of materials decreases by increasing the specimen size. Such a decrease can be remarkable when very large structures are considered. An overview of experimental findings and theoretical studies on this phenomenon is presented. Then size effect in fatigue is explained by considering the fractal nature of the reacting cross sections of t structures, that is, the renormalized fatigue strength is represented by a force amplitude acting on I a surface with a fractal dimension lower than 2. This dimensional decrement, which depends on a self-similar weakening of the material ligament, owing to the presence of cracks, defects, voids, etc. (microscopic level), tends to progressively disappear by increasing the structure size (macroscopic level), i.e. the effect of the material microstructure on the fatigue behaviour gradually finishes for relatively large structures (multifractality). Accordingly, two scaling laws for fatigue limit are herein proposed, and some experimental results are examined in order to show how to apply the theoretical approach presented.

Słowa kluczowe

EN

fatigue; size effect; fractal geometry; scaling law

• Czasopismo: Zeszyty Naukowe. Mechanika / Politechnika Opolska
• Rocznik: 2001
• Tom: z. 67
• Strony: 67-83
• Opis fizyczny: Bibliogr. 24 poz., tab., wykr.

Twórcy

autor

Carpinteri, A.

• Department of Civil Engineering University of Parma, Italy

autor

Landini, A.

• Department of Civil Engineering University of Parma, Italy

autor

Spagnoli, A.

• Department of Civil Engineering University of Parma, Italy

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