A local isotropic/global orthotropic finite element technique for modeling the crush of wood
Wood has often been used as the crushable material in impact limiters. However, the analysis of wood has been difficult because of its orthotropic crush behavior. A micro-mechanical technique for analyzing crushable orthotropic materials, such as wood, has been developed. Alternating layers of hard and soft isotropic material were used to produce global orthotropic behavior. This technique captured many of the phenomena observed with large crush of orthotropic materials. Crush stresses at different angles of loading with respect to the grain obtained with this technique compared well with Hankinson's empirical formula and with the Tsai-Wu failure criterion for orthotropic materials. Shear strain localizations, which have been observed experimentally in tests with loading parallel to the grain, were also predicted using the alternating layer model. In order to verify the constitutive behavior of the local isotropic/global orthotropic model, a parametric study of a simple wood sample crushed at different grain angles was performed. Following completion of the verification study, the technique was applied to the analysis of a transportation cask impact limiter that contained wood as part of its energy absorbing matrix. The analysis was repeated with an isotropic material model for comparison, and the differences between the results from the two studies will be discussed. 34 refs., 26 figs.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (USA)
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 6877229
- Report Number(s):
- SAND-88-1449; ON: DE89004663
- Country of Publication:
- United States
- Language:
- English
Similar Records
Characterizing large strain crush response of redwood
An orthotropic theory of viscoplasticity based on over-stress for thermomechanical deformation and its application to laminated metal-matrix composites
Related Subjects
420204* -- Engineering-- Shipping Containers
CASKS
COMMINUTION
CONSTRUCTION
CONTAINERS
CRUSHING
EVALUATION
HIGH-LEVEL RADIOACTIVE WASTES
IMPACT STRENGTH
IMPACT TESTS
MANAGEMENT
MATERIALS
MATERIALS TESTING
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
MECHANICAL TESTS
RADIOACTIVE MATERIALS
RADIOACTIVE WASTE MANAGEMENT
RADIOACTIVE WASTES
SPENT FUEL CASKS
TESTING
TRANSPORT
WASTE MANAGEMENT
WASTES
WOOD