Steel structure is mainly composed of horizontal structure and vertical structure. Horizontal structure system is bent (including roof truss, beam and column) as the basic bearing structure, to bear the roof under load, horizontal wind load, earthquake action, the vertical load and horizontal level of crane load.
Between the longitudinal structure system is made up of column, column support beams, walls, etc.
In addition, there are houses, walls and roof support, to form a space rigid frame.


A canopy is an overhead roof or else a structure over which a fabric or metal covering is attached, able to provide shade or shelter from weather conditions such as sun, hail, snow and rain.
Architectural canopies include projections giving protection from the weather, or merely decoration.
Such canopies are supported by the building to which they are attached and often also by a ground mounting provided by not less than two stanchions, or upright support posts.