ABSTRACT
In the last decades several researchers devoted their studies to the optimal design problem of structures subjected to quasi-static loads as well as to suitable combinations of fixed and dynamic loads (Rozvany 1989). These works contain original formulations characterized by different chosen objective functions, different admissibility conditions as well as different computational approaches. Recently, further design problem formulations have been proposed for elastic plastic structures subjected to appropriate combinations of fixed and seismic loadings simultaneously preventing different limit conditions (Giambanco et al. 2011). In the referenced formulations the dynamic response is evaluated by making recourse to a classical modal technique appropriately combining the single frequency responses.
