A basis for local minima of a symmetric frame topography

✍ Scribed by Y.A. Al-Salloum; G.H. Siddiqi

• Book ID: 104268603
• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 402 KB
• Volume: 51
• Category: Article
• ISSN: 0045-7949
• DOI: 10.1016/s0045-7949(05)80009-4

✦ Synopsis

AIMtract--Optimization of indeterminate frames involves non-convex stress constraint functions which form a non-convex design space that results in multiple local minima, unknown in number to begin with. The current state-of-the.art in this field recommends employment of different arbitrary initial designs to have a reasonable assurance ofreachlng every local minimum which, under a particular load, is associated with a specific material distribution. In this study a basis is laid down for (a) determination, at the very outset, of the number of local minima that possibly may exist in a frame of symmetric topography, (b) definition, in terms of relative member stlffnesses, of the material distribution pattern associated with each local minimum, and (c) a guideline for evaluation of member forces for initial proportioning of the pattern, The application of the proposed method for evaluation of local minima is illustrated with an example problem.