Fracture Analysis of Cracks in Complete Cylindrical Shells.
Abstract
This final tech report discusses fracture analysis contributions in the context of other activity on the problem of circumferential cracks in pipes or cylindrical shells. The circumferential through-crack problem in shallow cylindrical shells had been investigated by a succession of authors (Folias, Erdogan and Delale, Duncan and Sanders, and Simmonds). The solution, i.e. the determination of the stress intensity factors and/or the energy release rate had been established for the complete range of the parameters involved according to linear elastic fracture mechanics. However, it was not known how long the crack might be in relation to the circumference for the results to be valid, since the analyses were all based on shallow shell theory. In 1979 Barsoum et al. obtained results for long circumferential cracks in the complete cylinder by finite element methods. The calculations were necessarily for pipes of finite length and some unknown end effects were present. The present investigator published results (1982) obtained by a new analytical method for long circumferential through cracks in a pipe under axial tension. These results were in closed form and applied to pipes of infinite length. Research under the present contract began with similar calculations made for the pipe under combined bending and tension. Results obtained by this means agree quite well (in an overlap range) with previous results from shallow shell theory, and since the results were in closed form no 'parameter studies' were necessary.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 03, 1984
- Accession Number
- ADA150091
Entities
People
- J. L. Sanders Jr.
Organizations
- Harvard University