This is the main reinforcement provided to the structural element to resist the tensile stresses arising in the element due to the loads. In some cases, it is also used as a compression reinforcement, thus the concrete volume can be reduced to maintain the clear spaces for architectural purposes.
In addition to the primary reinforcement, secondary reinforcement provides an additional resistance in case of thermal expansions and it limits the crack developments thus preserves the aesthetic of the elements.
Links and stirrups
Again the steel is in use to control the shear forces arising on the structure due to the external loads. Usually 6mm, 8mm, 10mm and 12mm links are used for beams. In case of deep beams, where the existence of high possibility of torsional effects, 16mm links will be used.
Chairs or stools
Miscellaneous use of steel in the reinforced concrete structures are stools which are used to maintain the gap between top and bottom reinforcement.