Thin-Walled Beam Theories and Their Applications in the Torsional Strength Analysis of Ship Hulls.
Abstract
Unified developments of the St-Venant and warping-based thin-walled beam theories and their application in the torsional analysis of ship structures are presented. Open cell, closed cell and multi-cell configurations are treated. The warping-based torsional theory, which accounts for out-of-plane displacements and displacement restraints, provides axial stress distributions resulting from bimoments and in general offers improved predictions of shear stress distribution in thin-walled beams over the St-Venant theory; however, the use of that theory necessitates a more detailed cross sectional property evaluation. The generalization of the warping function to a displacement field independent of the twist is discussed, as are several iterative methods of including warping shear deformations. The application of the prismatic warping theory to the analysis of non-prismatic beams is discussed, and the flexural torsional beam method proposed by Pedersen is developed. This method, in conjunction with a computer program to calculate the required cross sectional properties, has been integrated into a general torsional stress analysis capability within Defence Research Establishment Atlantic (DREA). The DREA system, which can account for geometric discontinuities in a structure, has been developed as an alternative to finite element methods, and is evaluated here via comparison with detailed finite element analyses for several prismatic beams with discontinuities. The beam theory is applied to the stress analysis of the hull of a frigate. (Canada)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1987
- Accession Number
- ADA178296
Entities
People
- Thomas A. Vernon
- Y. Nadeau
Organizations
- Defence Research and Development Canada