Investigation of the coalescence of twin coplanar semi-elliptical fatigue cracks in structural steel elements under cyclic loading

  • 1 Ternopil Ivan Puluj National Technical University, Ternopil, Ukraine


The solution to the scientific task of identifying the fundamental laws of surface cracks development during their coalescence in the elements of steel structures under cyclic loading is presented in this article. A simulation model of coalescence of identical coplanar surface cracks has been developed. The model considers the solution to two problems: substantiation of the crack geometry during coalescence, and obtaining calculation formulas for estimating the stress intensity factors along a series of saddle-shaped contours. Based on the definition of stress intensity factors for contours modeling the gradual propagation of cracks in the coalescence zone using the finite elements method, the proposed model was tested to compare the calculated durability with experimental data.



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