一种等应力强度因子试件

A Constant Stress Intensity Factor Specimen

计算了含中心裂纹的矩形板(高为2H,宽为2W)的应力强度因子。板的对称面内距离为2y_0的两点承受大小相等方向相反的一对集中力P作用。采用的分析方法是含待定常数的复应力函数与广义变分原理相结合的方法。此复应力函数精确地满足裂纹表面的边界条件,其余边界条件由广义变分原理近似地满足。 当H=2W,y_0=0.3W,a=(0.2-0.45)W(a为半裂纹长度),计算结果表明,应力强度因子近似为一个常值,它取1.938P/(πW)^(1/2),相对误差小于0.75％。 若采用上述几何尺寸的试件测试疲劳裂纹扩展常数,将可大大简化试验程序和试验数据处理工作。

The stress intensity factors are computed for a rectangular plate containing a centrical crack with a height of 2 H and width of 2 W . The plate is subjected to two equal and oppo-site concentracted force P acting on two points a distance of 2 y0 in the symmetrical plane. The analytical method is based on complex stress functions containing constants to be de-termined in combination with generalized variational principles. The crack boundary condi-tions are satisfied exactly by complex stress functions and other boundary conditions are satisfied approximatively by generalized variational principles.When H=2W,y0=0.3W,α=(0.2-0.45)W (αis a half of the crack length).the calculations are shown that the stress intensity factors are approximatively a constant e-qual to 1. 938 with a relative error below 0.75%.