Optimal design of elastic-plastic structures

The optimal design problem for linear elastic structures has been the subject of abundant literature, and various behavioural constraints have been taken into account that very often concern structural deformation. On the other hand, the structural behaviour beyond the elastic limit has been considered in many papers dealing with optimal design for prescribed plastic collapse load (rigid-plastic models). Comprehensive surveys can be found, for istance, in Ref.s 1 to 5.