light weight floors and steel deck

huangyhg

light weight floors and steel deck
hi every one. i am searching about light weight floors, there is some new technology about it or the steel deck with concetre is the unique solution for this application? in addition, any one can tell me why does the moment or inertia in steel deck (technical tables) has the units of in4/ft? does it mean that if i have 2 or 3 feet lenght, i get 2 or 3 times the moment of inertia?
the units of in4/ft is per ft of width, not per ft of length.