When massed as reinforcing steel or reinforcement steel, rebar (short for reinforcing bar) is a steel bar or mesh of steel wires used as a tension device in reinforced concrete and reinforced masonry constructions to strengthen and help the concrete under tension.
About Reinforcing Steel
When massed as reinforcing steel or reinforcement steel, rebar (short for reinforcing bar) is a steel bar or mesh of steel wires used as a tension device in reinforced concrete and reinforced masonry constructions to strengthen and assist the concrete under tension. Concrete has a high compressive strength but a low tensile strength. The tensile strength of the structure is greatly increased by rebar. To encourage a better connection with the concrete and lessen the possibility of slippage, rebar’s surface is frequently “deformed” with ribs, lugs, or indentations.
Steel has a thermal expansion coefficient nearly equal to that of modern concrete. If this were not so, it would cause problems through additional longitudinal and perpendicular stresses at temperatures different from the temperature of the setting. Although rebar has ribs that bind it mechanically to the concrete, it can still be pulled out of the concrete under high stresses, an occurrence that often accompanies a larger-scale collapse of the structure. To prevent such a failure, rebar is either deeply embedded into adjacent structural members (40–60 times the diameter), or bent and hooked at the ends to lock it around the concrete and other rebar. This first approach increases the friction locking the bar into place, while the second makes use of the high compressive strength of concrete.
Hydraulic benders and shears are widely used to manufacture rebar cages on or off the project site. A tool known as a Hickey, or hand rebar bender, is sufficient for minor or specialised work. Steel fixers, sometimes known as “rodbusters,” or concrete reinforcing iron workers, insert the rebars with bar supports and concrete or plastic rebar spacers between the rebar and the concrete formwork to establish concrete cover and assure appropriate embedment. Spot welding, tying steel wire, utilising an electric rebar tier, or mechanical connections are used to link the rebars in the cages. Epoxy-coated or galvanised wire is typically used to tie epoxy-coated or galvanised rebars together.
Reinforcement placement in rolls
The roll reinforcement system is an incredibly quick and cost-effective way to place a significant amount of reinforcement in a short amount of time. Typically, roll reinforcement is made off-site and unrolled quickly on-site. BAM AG first presented the concept of roll reinforcement as BAMTEC Reinforcement Technology. Slabs (decks, foundations), wind energy mast foundations, walls, ramps, and other structures have all benefited from roll reinforcement deployment.
Mechanical connections, also known as “mechanical couplers” or “mechanical splices,” are used to join reinforcing bars together. For cast-in-place concrete construction, mechanical couplers are an excellent way to alleviate rebar congestion in highly reinforced sections. These couplers are also employed at the junctions between components in precast concrete construction.