I don't think there is a limit as such or even any rules you could look at for such a general question. I assume you mean reinforced concrete shells and domes. That covers a huge variety of shapes and structures. It will depend on loading, shapes, spans, etc. Obviously the larger the spans, the thicker the section required is likely to be and/or the heavier the reinforcement. Sorry, I can't be more specific without more information about the particular problem. Carl Bauer
Thank you for your answer The truth is that my question it is generic, your answer, also, but if you can recommend me some design parameters through web sites, books, etc., I will thank it to him
