Accession Number : AD0743507

Title :   Running Crack in an Incident Wave Field.

Descriptive Note : Technical rept.,

Corporate Author : LEHIGH UNIV BETHLEHEM PA INST OF FRACTURE AND SOLID MECHANICS

Personal Author(s) : Chen,E. P. ; Sih,G. C.

Report Date : MAY 1972

Pagination or Media Count : 67

Abstract : Steady-state diffraction of stress waves by a semi-infinite running crack is considered in this study. In conjunction with the principle of superposition, an exact solution is obtained by using a method based on the Wiener-Hopf technique. As in the static case, the dynamic stresses possess the familiar inverse square-root singularity at the crack tip. The stress-intensity factors, however, are found to depend on the incident wave length, angle of incidence, Poisson's ratio of the elastic solid and speed of crack propagation. The stress-intensity factor serves as a useful parameter in studying elasto-dynamic crack problems since it can be associated with the rate at which elastic and kinetic energies are released by the crack. Ductile fracture is studied by adapting the Dugdale's hypothesis. The length of the plastic zone is determined and the influence of the speed of crack propagation is displayed graphically. (Author)

Descriptors :   (*FRACTURE(MECHANICS), STRESSES), CRACK PROPAGATION, DYNAMICS, INTEGRAL EQUATIONS, PLASTIC PROPERTIES

Subject Categories : Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE