表面裂纹蠕变分析的蠕变线弹簧模型方法

鉴于用通常的数值方法分析三维蠕变裂纹问题的困难，提出了一个三维表面裂纹蠕变断裂力学参量分析的蠕变线弹簧模型方法，并在非稳态蠕变条件下的位移、裂纹尖端J积分和C积分的工程估算公式及弹塑性线弹簧模型的基础上，建立了蠕变线弹簧模型方法的有关基本方程．具体分析计算了受均匀拉伸表面裂纹平板的J积分和C积分，并与三维有限元解进行了比较，其结果吻合良好．研究结果为进一步研究三维表面裂纹的蠕变扩展及寿命预报提供了基础．

THE CREEP LINE-SPRING MODEL FOR CREEP ANALYSIS OF SURFACE CRACKS

Considering the difficulty of creep analysis of the three-dimensional cracks by the common numerical methods, this paper proposes a creep line-spring method (CLSM) for the estimates of creep fracture parameters for the creep surface cracks. The fundamental equations of the creep line-spring method are established on the bases of the approximate solutions of the non-steady creep crack and the elastic-plastic line-spring method. Several numerical examples for the creep fracture parameters, J and C integrals, of the surface-cracked plates under uniform tension are shown. The results airs well agreement to the ones of the three-dimensional finite element method.The proposed creep line-spring method provides the basis for the further studies on the creep growth of three-dimensional cracks and the creep residual life estimates for the cracked structures.The concerned studies are currently under investigation.