Fracture Mechanical Behavior Of Cracks Emanating From An Elliptical Hole

The hole-edge crack is one of the most common cracks in practical engineering structures,and it is an important factor affecting structural integrity.Therefore,in-depth study of the hole-edge crack problem has important practical significance.In the fracture mechanics analysis of the hole-edge crack structures,the stress intensity factor,plastic zone and open displacement at the crack tip are important parameters.At present,there are many methods to study the parameters related to the hole-edge crack,and the complex variable function method is an efficient and accurate method.Therefore,it is necessary to use the complex variable function method to further study the problem of an elliptical hole with two straight cracks,and obtain the solutions of these three parameters,which provides some guidance and promotion for engineering practice.In this paper,the infinite plate problem of an elliptical hole with two straight cracks is studied,and the analytical solution of the stress intensity factor at the crack tip is given.The numerical solution of the stress intensity factor is obtained by using ANSYS.The Mises yield criterion method and the D-M model method are used to obtain the plastic zone and open displacement of the crack tip.The results obtained by the two methods are compared.The variations of stress intensity factor,plastic zone and open displacement with elliptical hole size and crack length are studied.The results show that under the normal load and the biaxial tensile load,the stress intensity factor at the crack tip increases with the increases of the ratio of the major semi-axis to the minor semi-axis of the elliptical hole and the length of the crack,and decreases with the increases of the minor semi-axis.Under the far-field uniform tensile load,the plastic zone length and the open displacement of the crack tip increase with the increases of the crack length,and decrease with the increases of the minor semi-axis length of the elliptical hole.The analytical solution of the stress intensity factor at the crack tip is in good agreement with the numerical solution.The results of the plastic zone and open displacement of the crack tip obtained by the Mises yield criterion method are agree well with the results of the D-M model method.