运用损伤力学求解金属构件疲劳裂纹形成寿命的附加位移法

 从损伤力学出发，建立了对金属构件疲劳裂纹形成过程进行损伤耦合的弹塑性应力分析及寿命估算的附加位移法。该方法较充分地利用了缺口构件疲劳损伤的局部性特点，其计算量远低于普通的全场数值解法。算例表明寿命的理论解与试验值基本吻合。该方法对于分析其他局部耦合问题也具有参考价值

ADDITIONAL DISPLACEMENT METHOD FOR PREDICTION OF FATIGUE CRACK INITIATION LIVES OF METALLIC STRUCTURES BASED ON DAMAGE MECHANICS

The additional displacement method is developed for damage coupled elasto plastic stress analysis and life estimate for metallic structural components in the process of crack initiation. Damage is described with a scalar. The basic formulation is established in terms of the range of variation about related fields. The damage of the critical point is regarded as a generalized time scale instead of the cycle number. The local behavior of damage is rather fully used in the study of notched sheets. The required integration is performed only within the damage zone and the damage influenced zone, which are only small parts of the structure configuration. The amount of computational work of this scheme is much less than that of ordinary numerical analysis of the whole field. Examples show that the computed results agree well with experimental ones. This approach exhibits some referential value for solving other problems with locally coupled effects.