PSI - Issue 41

Yu.G Matvienko et al. / Procedia Structural Integrity 41 (2022) 192–198 Author name / Structural Integrity Procedia 00 (2019) 000–000 is attributed to the definition of limiting values of the damage accumulation function. The required procedure is based on the use of normalized distribution of each damage indicator � � � � as a function of cycle number, which are constructed in the range from � = 0 to � � ��� . These dependencies are presented in Fig. 4. 197 6

Fig. 4. Evolution of normalized deformation parameters. A square lying under each normalized � � curve, shown in Fig. 4, are represented by itself initial experimental information which is essential for calculation of the coefficient �� � � . This square is denoted as ∑ � � . Required coefficients are derived as an inverse proportional values: �� � � � �� ∑ � �. (5) The developed procedure leads to an explicit form of the damage accumulation function. Graphical representation of the data following from formulae (4) and (5) for the construction of an explicit form of the damage accumulation functions is shown in Fig. 5.

Fig. 5. Damage accumulation functions based on different damage indicators.

Lines presented in Fig. 5 clearly evidence the same damage accumulation functions, which follow from three