Effect of small recesses and swellings on cohesive crack growth in stretched by two concentrated forces plate

• Main Author: Гасанов, Шахин
• Format: Article
• Language: Russian
• Published: Journal of Mechanical Engineering 2015
• Subjects: crack with bonds between the faces; retardation of cohesive crack; thin isotropic plate; concentrated forces; УДК 539.375; трещина со связями между берегами; торможение когезионной трещины; тонкая изотропная пластина; сосредоточенные силы; тріщина зі зв’язками між берегами; гальмування когезійної тріщини; тонка ізотропна пластина; зосереджені сили
• Online Access: https://journals.uran.ua/jme/article/view/39208

An isotropic thin plate of everywhere constant thickness, except for some S1 and S2 areas on prolongation of the rectilinear crack with bonds between the faces near the crack ends, is considered. The plate is stretched by two concentrated forces. It is assumed that the fracture process is localized in the end zone, which is considered as crack part and can be comparable to crack size. We investigate the plane fracture problem of cohesive crack retardation by small changes in the material thickness on the crack growth path. The boundary value problem for the equilibrium of the cohesive crack in the plate under the action of external tensile forces is reduced to solving of nonlinear singular integral equation. Using the Gauss-Chebyshev quadrature formulas, the singular integral equation reduces to a finite algebraic system that solving by iterative algorithm similar to the Il’yushin’s method of elastic solutions. From the solution of the nonlinear singular integral equation the stresses in the bonds are found. The most widely distributed in the practice forms of the recesses and swellings are considered. The considered examples demonstrate the new effects of the retardation and stable development of through cohesive cracks, only caused by variable plate thickness on the crack ends.