Development and Background of Shells Theories-A Review Study

Thin shells are one of the structural elements that have versatile contributions in different engineering sectors,specifically in architectural,civil,mechanical,aeronautical,and marine engineering industries.Liquid-retaining structures,wide-span roofs,water tanks,arch dooms,and shells used in building nuclear power plants are recognized application examples of shell structures in architectural and civil engineering.This variety in using shells in different engineering sectors is due to the productivity of load-carrying behavior,excellent reservation in strength and structural integrity,shell structures are preferable in comparison to structural systems having the same span and dimensions;high stiffness,and covering a large areas.Besides the above distinguishing mechanical pros,it is widely accepted that structures and building containing shells are usually preferred by architectures and designers for aesthetic purposes.The analysis of shells has gone through many stages until the arrival of modern theories.In this study the different theories of shells were discussed,the background and development of shell theories were illustrated in this investigation.