Original paper(Vol.49 No.2 pp.175)

Calculation on stress intensity factor by V-line hybrid extrapolation method - application to finite element analysis

Fujisaki Wataru; Komiya Makoto; Tanaka Satoshi

Abstract:One of the authors has derived K (r, q), namely the equation of extrapolation curve in a series and proposed a new short-cut method called V-line extrapolation method. Also, it was reported there are the specific angles at which we can obtain an accurate stress intensity factor by using boundary element analysis. In this paper, an application of the V-line hybrid extrapolation method was conducted to finite element analysis by an approximate angle which is easy to use. At first, it is found that the accuracy of S.I.F is considerably improved by using the angles, I.e. sy at q = p/2, txy at q = p/4 in a plate with a central slant crack under remote tension. Furthermore, the effects of element types to the accuracy were discussed. It is clarified that the accuracy for KI by the V-line hybrid extrapolation method applying to 4 nodes-element is much better than the one by the conventional method applying to 8 nodes-element.

Key Words:Stress intensity factor, Finite element analysis, Extrapolation method, Hybrid extrapolation method, V-line extrapolation method