Development of Mathematical Model for Detection of Conditional Sizes Primordial Cracks in LEFM and Its Implementation in Russian Cax System

摘要

This paper addresses the definition of conventional primordial crack size by solving the inverse problem of traditional LEFM and implementation of this tool in the Russian CAx system APM WinMachine. The condition of the primordial origin of the crack with the principal stresses and classical criteria of strength are shown. A mathematical model for finding the conditional size of the crack is shown. The critical value of the parameter of fracture mechanics-the stress intensity factor (SIF) and the value of the stress concentrator are used for this purpose. The critical value of SIF was defined by experiment. A mathematical model has been implemented in the Russian CAX system APM WinMachine which uses a numerical finite element method (FEM). Output data (crack dimensions) of the mathematical model are used in solving the analytical problem to determine the SIF. The validity of the numerical and analytical calculation of the data is checked by comparing the SIF critical value obtained experimentally, with the analytical one. The calculations were performed on the example of solving the static problem with a different loading step.