Acta Metallurgica Sinica (English Letters) ›› 2010, Vol. 23 ›› Issue (1): 41-49.DOI: 10.11890/1006-7191-101-41

• Research paper • Previous Articles     Next Articles

Effect of three dimensional stress state on unstable fracture  condition and crack opening level in a new crack growth model

Fang WANG,Weicheng CUI   

  1. China Ship Scientific Research Center,Wuxi 214082, China
  • Received:2009-04-23 Revised:2009-06-21 Online:2010-02-25 Published:2010-02-09
  • Contact: Fang WANG

Abstract:

A new model for the analysis of fatigue crack growth in the metal structures was proposed. This model shows a promising capability of explaining various fatigue phenomena. The new crack growth model is further completed by a continuous empirical formula for estimating the value of variable fracture toughness during crack propagation and a modified continuous equation for the crack tip stress/strain constraint factor used to calculate the stress intensity factor at the opening level. The prediction results are proved to agree well with the observed phenomena in test.

Key words: Marine structures, Crack growth rate, Three dimensional stress state, Fracture toughness, Crack tip stress/strain constraint