表面附近I型非对称裂纹扩展路径的评价

On the growth track of asymmetrical I-crack near surface

为了解决有限几何体表面附近I型非对称裂纹的扩展方向与扩展轨迹问题,以弥补工程断裂力学理论在有关问题研究中的不足,以端部开有一不对称纵向裂缝的悬臂梁为研究对象,分析了悬臂梁端部的裂缝两侧受到横向荷载作用下,裂缝端部附近的应力场特征以及裂缝可能的扩展轨迹.通过材料力学与线弹性断裂力学理论的结合,解析了平面条件下,有限几何体表面附近I型非对称裂纹的扩展机理及弧形扩展轨迹.建立起一个比较符合表面附近I型非对称裂纹扩展路径的数学力学模型.利用该模型,可以从理论上有效地分析有限几何体表面附近I型非对称裂纹的扩展路径.

In order to solve the problem with the growth orientation and track of asymmetrical Ⅰ-crack near the surface of finite geometric solid, and to remedy the defect of engineering fracture mechanics by which the relative problem is studied, this paper takes the object of a cantilever beam where a asymmetrical lengthwise crack is the end, and the stress field near the crack tip and the probable growth track of the crack have been analysed when transverse loads are acted on both sides of the crack, The growth mechanism and the track of asymmetrical Ⅰ-crack near the surface of finite geometric solid in plane condition are analysed by combining material mechanics and fracture mechanics. Finally a mathematical-mechanical model that can be approximately adapted to express the growth path of the crack was established, And therefore the growth path of the crack can be analysed availably theoretically,