Acoustic emission and dynamic energy re1ease rate for steady growth of a tunneling crack in a plate in tension

摘要

The dynamic steady state growth of tunneling cracks in membrane loaded isotropic Kirchhoff plates is considered. Explicit solutions for the asymptotic displacement and velocity fields are presented. It is shown that the asymptotic fields are inversely proportional to the square root of distance from the crack tip, and that a wake may or may not develop behind the crack tip depending on the static membrane state. If the crack tip velocity is smaller than a certain critical velocity, the asymptotic solution will completely vanish. An explicit solution for the dynamic energy release rate is also presented. Due to elastic waves radiated from the crack tip, the dynamic energy release rate wil1 generally be smaller than the corresponding static energy release rate.