Deformed Steel bars: Definition and types
What is Rebar?
Deformed steel bars, also known as reinforcing bars or rebars, are a critical component inconcrete construction. They have surface deformations in the form of ribs, lugs, orindentations to enhance their bonding with concrete. These deformations improve themechanical properties and performance of reinforced concrete structures.
Steel reinforcement bars or rebars are used to improve the tensile strength of theconcrete, since concrete is very weak in tension, but is strong in compression. Steelis only used as rebar because elongation of steel due to high temperatures (thermalexpansion coefficient) nearly equals to that of concrete.
Types
►Hot-Rolled Deformed Bars (HRB): These bars also known as thermo-mechanicallytreated bars are manufactured by hot-rolling, where steel billets are heated andpassed through a series of rollers to create the desired deformations. Hot-rolleddeformed bars are available in various qrades and sizes.
►Cold-Worked Deformed Bars (CRB): Cold-worked bars, also known as high-strength deformed bars or cold-drawn bars, are produced by stretching or drawinghot-rolled steel bars through a series of dies to create the deformations. They have asmoother surface compared to hot-rolled bars.
Characteristics
Deformed steel bars have a pattern of deformations on their surface, which can bein the form of ribs, lugs, or other irregular shapes. These deformations create amechanical bond with the surrounding concrete, preventing slippage and improvingoad transfer between the steel and concrete.
Deformed bars have high tensile strength, which is essential for reinforcing concretestructures. The deformations enhance the bond between the rebar and the concreteenabling the concrete to carry tensile forces effectively.
Deformed steel bars are designed to have good ductility, allowing them to deformwithout sudden failure under high stress. This ductility is crucial in applicationswhere the structure needs to absorb energy during stress events.
Deformed bars are manufactured according to international and national standardsensuring quality and consistency in their properties and dimensions. Commonstandards include ASTM A615 (USA), BS 4449 (UK), and ls 1786 (India).
Benefits
1. The deformations on the surface of deformed steel bars significantly improve thebond between the rebar and concrete. This enhances the structural integrity ofconcrete structures, especially under tension.
2. Deformed bars offer a higher load-carrying capacity compared to plain (smooth)bars. This is crucial in applications where the concrete needs to bear heavy loads andresist stresses.
3. Deformed bars are ductile, providing resilience and flexibility to concrete structuresmaking them better equipped to handle dynamic loads and seismic events withoutabrupt failure.
4. Deformed bars contribute to the stability and safety of structures, making themsuitable for use in a wide range of applications, including buildings, bridges, roadsand other infrastructure.
5. Deformed bars are manufactured in accordance with industry standards, ensurinoquality, consistency, and compliance with engineering requirements.
T'ypes of Steel Reinforcement Bars
Mild Steel Bar
The surface of the mild steel bars are plain and round in shape. They are availablein various sizes of 6 mm to 50 mm, They are used in concrete for special purposes,such as dowels at expansion joints, where bars must slide in a metal or papersleeve, for contraction joints in roads and runways, and for column spirals. Theyare easy to cut and bend without damage.
Grades in mild steel bars
Mild Steel Bars
Mild steel bars grade-l designated as Fe 410-S or Grade 60.
Mild steel bars grade-ll designated as Fe-410-0 or Grade 40.
Deformed Steel Bar
Deformed steel bars have ribs, lugs and indentation on the surface of the bar, whichreduces the major problem that is faced by mild steel bar due to slippage and goodbonding is achieved between concrete and rebar. The tensile properties is highercompared to other rebars. These bars are produced in sections from 6 mm to 50mm dia.
Characteristics of TMT Rebars
◆Better ductility and malleability
◆High yield strength and toughness
◆More bonding strength
◆Earthquake resistance
◆Corrosion resistance
◆High thermal resistance
◆Economical and safe in use
◆No loss in strength at welded joints
◆Ordinary electrodes used for welding the joints
We are always at your service when you need
Xi'an Dongmeng Steel Co., Ltd. is a well-known enterprise in the international steel market.which is certifed by SGS Group. lt focuses on providing high-quality steel bars, steel pipesand steel coils to customers around the world, Since its establishment, we have beenadhering to the business philosophy of"quality-oriented, integrity-first", constantly pursuingexcellence and innovation, and committed to building a world-eading steel supply chainservice system. Our customers are all over the world.
active members
years experience
events & challenges
expert instructor
Our address
Room 4107, Runfeng Building, Sanqiao New Street, Weiyang District, Xi'an City, Shaanxi Province
Phone Number
+86 15769214734
