See text book by Prof.Robert D.Cook, Concepts and Applications of FEM, John Wiley and Sons, 2000. He has a chapter on Shell elements.
Dr.P.Jayachandran, WPI, Worcester, Mass, 01609. Structural Engineering is the art and science of judiciously proportioning elements and systems to carry loads in an optimum fashion. Stress analysis, static, dynamic and non-linear, essentially enables the design. Aesthetics and economics play a complementary role in design-with constructability or feasiblity included.
Prof.Jay, WPI