This term is applied to various kinds of physical structures such as buildings, bridges, or ships.
The height and the weight of superstructure on board a ship or a boat also affects the amount of freeboard that such a vessel requires along its sides, down to her waterline.
In broad terms, the more and heavier superstructure that a ship possesses (as a fraction of her length), the less the freeboard that is needed.
The span of a bridge, the portion that directly receives the live load, is referred to as the superstructure.
[2] In order to improve the response during earthquakes of buildings and bridges, the superstructure may be separated from its foundation by various civil engineering mechanisms or machinery.