Dynamic elastic-plastic fem analysis of a fracture specimen under plane stress state

✍ Scribed by Rao Shiguo; Xia Yuanming

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 562 KB
• Volume: 52
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(94)00209-z

✦ Synopsis

A novel method for measuring plane stress dynamic fracture toughness was presented by Xia et al. 48 17-24 (1994)]. A formula for calculating dynamic J-integral (J*) from the measured average load-displacement behavior was introduced by extending the quasi-static deep crack formula proposed by Rice et al. In this paper, we have carried out the dynamic FEM analysis of the specimen with double notches used in Xia et al. [1]. The specimen is subject to the experimentally measured tensile pulse at two ends. The J(t) integral due to Kishimoto is employed to calculate the dynamic energy release rate. We also compute the value of J-integral (Jd,.) from the measured load--calculated displacement curve by the formula proposed in ref. [1]. For three specimens with different crack lengths 3.5 5.0 mm, the three J-integrals J, J~,. and Jac are almost the same from the start point of loading to the crack initiation point C (the maximum difference between them is 5.0%). Our analysis results confirm that J-integral can be used as the crack tip characterizing parameter of the fracture specimen used in experimental system in ref. [1], and the formula proposed in ref.

[1] for calculating J-integral from dynamic load~lisplacement behavior is useful and with high accuracy. The present investigation provides a further demonstration of the method proposed in ref. [1] for characterizing and measuring the plane stress elastic-plastic dynamic initiation fracture toughness.