Boyko V. Calculation dynamic stress intensity factors for specimen with crack

Object: natural frequencies of free vibrations of beam and cylindrical specimens with cracks and eigenfunction accordingly, dynamic stress intensity factors (DSIF). Aim: approximated analytical formulas construction for calculation DSIF in beam and cylindrical specimen under different load conditions. Methods: mechanical methods of fragile fracture, linear mechanical vibrations theories, finite elements, linear algebra, least squares. Results: calculation technique DSIF in finite dimensional bodies with crack was developed; for wide range of input parameters dependence DSIF on time for beam and cylindrical specimen under different load conditions was got and appropriate approximated dependence was constructed that gives a possibility to simplify a procedure of processing experimental data on testing materials for dynamic fracture strength. Novelty: for the first time approximated formulas for DSIF in beam and cylindrical specimen under different load conditions was constructed. Application: Research results were used in efficient national standard of Ukraine DSTU 4675:206 elaboration. Usage: Scientific-researching and engineering centers investigate dynamic fracture strength constructional materials.