孔边线状裂纹断裂扩展的研究

本文通过叠加原理和梅林(Mellin)变换,将无限弹性体内孔边线状裂纹的控制方程和边界条件化成对偶积分方程,又通过希尔伯特(Hilbert)有限变换,将对偶积分方程化为关于S(t~2)的第二类弗雷德霍姆(Fredholm)积分方程。通过弗雷德霍姆积分方程的解表示了孔边裂纹扩展时的动态应力强度因子,并得出了数值结果。在特殊情况下,数值结果与文献〔2〕的结果相吻合。应力强度因子随着裂纹的扩展而下降。同时,通过实验,测定了孔边线状裂纹的断裂扩展速度。

The Study of Propagation of Linear Cracks Intersection Hole

In this paper, the superimposing principle and the theory of Mellin transforms are used to reduce the controlling equations and boundary conditions of linear cracks intersecting hole into dual integral equations in an infinite elastic body. With finite Hilbert transforms, the dual integral equations can be reduced into a Fredhole integral equation of the second kind which is related to S(t2 ). The dynamic stress intensity factor can be expressed with the solution of integral equation and its numerical results in obtained. In the particular case, the numerical results are the same as those in reference2] . the intensity factor decreases with the propagation of cracks. With experiments, the propagation velocity of these linear cracks are measured.