A uniform model, in which the crack, V-notch, U-notch and arc are described as breach uniformly, is put forward in this paper. The tip radius, depth and field angle of breach are regarded as the parameter of annularly breached bar. The stress field and displacement field near the tip of the annularly breached bar under bending, in which takes fα(a/b) as its descriptive parameter, was given. All forms of breaches according to the change of tip radius, depth and field angle were discussed. The effects of parameters on fα(a/b) in bending were analyzed. The criteria for the safety design and fracture design both of which on fα(a/b) were obtained. The results not only can be applied widely to anti-fracture design but also be used for reference in anti-fatigued design in product lifecycle management.