A Disc-Shaped Interface Crack in a Laminated Plate Subject to a Uniform Temperature Change.

Abstract

Symmetrical bending of a circular laminated plate containing a disc-shaped delamination subjected to uniform temperature change is analyzed on the basis of the theory of small deflection of plates. Radial inplane forces induced by bending in the parts of the plate above and below the delamination are determined by regarding the cracked part as two lapped discs hinged at both edges. For small temperature change, the plate deflects retaining mutual contact of crack faces, and in this case energy release rate is identically zero. For temperature change that is larger than some critical value, local delamination buckling occurs and the energy release rate is no longer zero. It is shown that, when the critical energy release rate concept of Griffith is adopted, the disc-shaped delamination grows unstably under constant temperature condition.