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对于平面应力状态下,在Huber-Mises型弹性-理想塑性材料中Ⅰ型裂纹定常扩展时裂纹尖端附近应力应变场的渐近分析问题作了评述。指出:仅仅应力场的主项不能完全确定奇性应变区中的应变场主项。在等应力塑性区内,应变速率不可能具有1nr/r奇性。有限元数值解、裂纹试样表面实验观测与现有渐近分析表达式在某些方面的一致表明基于平面问题表述来解决此问题仍然是有希望的。但是,采用考虑到厚度变化的某种广义平面应力表述看来是必要的。
The problem of asymptotic analysis of stress-strain field near crack tip in the Huber-Mises elastic-ideal plastic material under normal stress state is reviewed. It is pointed out that only the principal component of the stress field can not completely determine the main field of strain field in the singular strain region. In the same stress-plastic zone, the strain rate can not have 1nr / r singularity. The finite element numerical solution and experimental agreement between the cracked sample surface and the existing asymptotic analysis expression in some aspects show that there is still some hope to solve this problem based on the planar problem expression. However, it seems necessary to adopt a generalized plane stress formulation that takes account of the thickness variation.