Brittle Fracture of Structures Elements with Stress Concentrators

The results of experiments on the brittle fracture of ebonite disks with a central hole are presented. Discs were compressed on diameter between steel plates. The values of the critical stress intensity factor and the tensile strength of ebonite were determined. To analyze the stress state before brittle fracture used solutions of the linear theory of elasticity. A comparison of results obtained using both local and nonlocal fracture criteria (the integral and the gradient), with experimental data is carried out. It is shown that the integral and gradient criteria give higher estimates of limit loads and better describe the experimental data in comparison with local criterion.