The design of structures for buildings and bridges is mainly concerned with the provision and support of horizontal surfaces. In buildings, the floors are usually made of concrete, reinforced by steel to resist tension. As span increase, it is cheaper to support the slab, by beams, rather than to thicken the slab. In building structures the grid of beams is in turn supported by columns. Both the beams and columns can be conveniently constructed using structural steel sections.
The materials which are usually used for structural purposes are cast-iron, wrought-iron and steel. Cast-iron can take up only compressive stresses and its use is limited to compression members only. Wrought-iron is of a fibrous nature and it is suitable to resist tensile stresses. Mild steel is suitable for all constructional purposes in general and hence, it has practically replaced cast-iron and wrought-iron in the present day practice of building construction.
Framed structures of R.C.C. and steel are becoming very popular at present. It is possible to construct a framed structure with a combination of R.C.C. and steel.
Participants