Steel Reinforcement Bars Properties
Steel Reinforcement is a vital component of reinforced concrete structures. It is designed in such a manner that the steel and concrete function jointly to resist induced forces on RC structure.
The characteristics of thermal expansion for steel and concrete are almost equivalent, minimum up to a greatly high temperature, together with this steel containing its superior bendability property and strength to resist tensile load to manage shortcoming of concrete to sustain tensile load, produces the standard material as reinforcement in concrete structures.
In normal reinforced concrete structures, the steel bars utilized as reinforcement are called passive reinforcement, also defined as rebars. In pre-stressed concrete structures, the reinforcement (steel wires) are stressed before exposing the structures to loading that may be defined as active reinforcement.
Cold twisted deformed (CTD) rebars are also very useful. They contain yield strength in the range of 405 MPa (Grade-40). Tor steel is the trade name of these bars.
Tor steel alias Tor-40 with characteristic (yield) strength of 415 N/mm2 (or 415 MPa) is very inexpensive as compared to mild steel since the weight of steel reinforcement can be decreased significantly for equivalent design loads, because of almost 65% greater strength.
Thermomechanically treated (TMT) rebars can create greater strength rebars up to 500, 550 or even up to 600 MPa.
Stainless steel rebars contain greater chromium content and it has good anti corrosive feature.
Some vital features of rebars :-
- Strong strength for creating cost-effective design of RCC structure.
- Tight gripping with concrete i.e. good bonding.
- Thermal expansion characteristics are well suited with concrete.
- Sound ductility to resist cyclic bonding (as for instance earthquake loading) or impact.
- Superior bendability that is required for providing perfect shape to rebars to satisfy the demand of the structures.
- Superior weldability for simplifying good reinforcement cage binding and saving of lap length.
- Sound resistance strength against corrosion to enhance the longevity of RCC structure.