摘要
Based on the viewpoint that there are similarities to the genetic principles in the mechanics and the engineering fields; based on data in some referents and author＇s theoretical approach, this paper is to consider the microscopic-damage and the macroscopic-damage behaviors of materials that are distinct differences, thereby to propose computing models and methods of subsection calculations in whole process; to consider the behaviors between the short cracks and long ones both of which are always continuous, thereby to propose some computing models and methods of the successive calculations. These computing models refer to formulas of the threshold sizes of cracks （or threshold values of damages）; the propagating rates of cracks; the predicting calculations of lifetime; Particularly, in which it provides a best new comprehensive figure that it could be including mid describing all problems mentioned above. So it may be as a bridge to link the traditional material mechanics, the material discipline and the modem mechanics on fatigue-damage-fracture; perhaps, it can also be as route diagram to guide designs and calculations to some materials and structures. Therefore, above works realize calculations of the strength problems, the growth rate of cracks （damages） mid prediction of lifetime in whole process that would have practical significances.
