CALCULATION OF THE STRESS INTENSITY FACTOR AND ESTIMATION OF ITS ERROR BY A SHAPE SENSITIVITY ANALYSIS

The precision with which the stress intensity factor (SIF) can be calc ulated from a finite element solution depends essentially on the extra ction method and on the discretization error. In this paper, the influ ence of the discretization error in the SIF calculation was studied an d a method for estimating the resulting error was developed. The SIF c alculation method used is based on a shape design sensitivity analysis ; this assures that the resulting error in the extracted SIF depends s olely on the global discretization error present in the finite element solution. Moreover, this method allows us to extend the Zienkiewicz-Z hu discretization error estimator to the SIF calculation. The reliabil ity of the proposed method was analysed solving a two-dimensional prob lem using an h-adaptive process. Also the convergence of the error wit h the h-adaptive refinement was studied.