Fundamentals of exact multi-load topology optimization --- stress-based least-volume trusses (generalized Michell structures) --- Part I: Plastic design

In this two-part paper, Michell's century-old stress-based single-load truss topology optimization paper is extended to multiple load conditions. In Part I, so-called `optimal plastic design' of multi-load trusses is reviewed, which is based on ultimate (limit or collapse) load principles and requires only statical admissibility of the solution. However, its connections to `optimal elastic design' will be explained, and these will be used in Part II for the full extension of Michell's theory to elastic multi-load problems, which will fill a significant gap in our knowledge.