Solution of Stress Intensity Factor and Its Sensitivity Analysis of Notched Semicircular Bend Specimens

To explore the solution of the dynamic stress intensity factor (SIF) of the fracture model I, static and dynamic three-point bending numerical tests on the notched semi-circular bend (NSCB) specimens were conducted by using Abaqus software. The method of dimensional analysis was used to fit the K-factor formula of the fracture model I under static loading. Then this expression was extended to solve for the stress intensity factor under dynamic loading. The SIF was analyzed with the relative crack length a/R (a is the crack length, R is the radius of the specimen) and S/R (2S is the simply supported distance of the specimen) under static loading conditions, and the effects of the stress pulse duration and wave shape on achieving dynamic force equilibrium were analyzed under dynamic loading. Results show that the static SIF increase with the increase of a/R and S/R, and the triangular stress pulses during 200 μs, 300 μs and 400 μs have similar trends with the trapezoidal stress pulses in achieving stress uniformity in the specimens. When the dynamic equilibrium is achieved under dynamic loading, the curve of dynamic SIF with time derived from the static K-factor formula has a smaller error compared with the results obtained by the dynamic finite element method. The conclusions obtained provide a significantly reference for the fracture analysis © 2021 School of Science, IHU. All rights reserved