STABILITY ANALYSIS OF COMPLEX STRUCTURES USING DISCRETE ELEMENT TECHNIQUES.
Abstract
Stability analysis of structures idealized into an assembly of discrete elements is presented, using both the matrix displacement and matrix force methods. This analysis is particularly suitable in determining loading conditions for buckling of complex structures for which the conventional methods can not easily be applied. In the displacement method geometric stiffnesses are introduced to form the eigenvalue equations for buckling while in the force method the same equations are obtained by introducing fictitious forces and deformations on structural elements. A general method for determining geometric stiffnesses for arbitrary structural elements is derived. This method allows for a systematic inclusion of different nonlinear terms from the strain-displacement relations and is considerably simpler than the conventional techniques requiring the determination of strain energy. To demonstrate the method, geometric stiffnesses are derived for bars, beams, and triangular and rectangular plates with membrane stresses. A new geometric stiffness matrix for the rectangular plate element with bending deformations is also derived and the results are used to determine buckling stresses of flat rectangular plates with various aspect ratios and boundary conditions. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1967
- Accession Number
- AD0663919
Entities
People
- J. S. Przemieniecki
Organizations
- Air Force Institute of Technology