Path-Independent Integrals and Fracture Mechanics
Abstract
The rational and economic design of aerospace structural systems and components presupposes the ability to perform a fracture mechanics analysis in an efficient and reliable manner. Such an analysis, to assure structural integrity, has to take account of complex loadings (both static and dynamic) as well as thermal and other environmental conditions to which many such systems are subjected. Using a variational principle with varying boundaries, it was shown that both physical and material conservation laws can be obtained from the same expression. The basic quantities used in these conservation laws are the physical momentum (stress) and material momentum. Two different representations were employed to study the equal importance of both of them in elastic materials and structures. In addition, by a suitable choice of the Lagrangian, the balance laws of moment of material momentum was derived directly by considering rotations in material space. This permitted then also to derive the balance law connected with similarity and establish the relation between these balance laws and path-independent integrals of fracture mechanics. Further, a suitable form of the Lagrangian was found which permits to establish conservation laws for thermoelasticity. Keywords: Crack propagation. (AW)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1983
- Accession Number
- ADA215333
Entities
People
- A. Golebiewska-herrmann
- G. Herrmann
Organizations
- Stanford University