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Steel has an expansion coefficient nearly equal to that of modern concrete. If this weren't so, it would cause problems through additional longitudinal and perpendicular stresses at temperatures different than the temperature of the setting.[2] 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 precedes 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.
Common rebar is made of unfinished tempered steel, making it susceptible to rusting. Normally the concrete cover is able to provide a pH value higher than 12 avoiding the corrosion reaction. Too little concrete cover can compromise this guard through carbonation from the surface. Too much concrete cover can cause bigger crack widths which also compromises the local guard. As rust takes up greater volume than the steel from which it was formed, it causes severe internal pressure on the surrounding concrete, leading to cracking, spalling, and ultimately, structural failure. This is a particular problem where the concrete is exposed to salt water, as in bridges built in areas where salt is applied to roadways in winter, or in marine applications. Epoxy-coated, galvanized or stainless steel rebars may be employed in these situations at greater initial expense, but significantly lower expense over the service life of the project. Especially epoxy-coated have to be installed with great care, because even small cracks and failures in the coating can lead to intensified local chemical reactions not visible at the surface.
Fiber-reinforced polymer rebar is now also being used in high-corrosion environments. It is available in many forms, from spirals for reinforcing columns, to the common rod, to meshes and many other forms. Most commercially available rebars are made from unidirectional glassfibre reinforced thermoset resins.
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http://en.wikipedia.org/wiki/Rebar
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What is TMT Re-Bars?
Thermo mechanical tempered Reinforcing bar or Structural steel
Is re-bar and reinforcement bar is same?
Yes.A rebar, or reinforcing bar, is a common steel bar, and is commonly used in reinforced concrete and reinforced masonry structures. It is usually formed from carbon steel, and is given ridges for better mechanical anchoring into the concrete. It can also be described as reinforcement or reinforcing steel. In Australia, it is colloquially known as reo.To know more about rebar visithttp://en.wikipedia.org/wiki/Rebarhttp://www.rgsrebar.com
Why steel is called rebar?
It's simply hardened steel that's been cast in long rods. It's used as reinforcing when pouring concrete to increase the strwength - especially in road construction or building foundations.
What is a y12 reinforce steel bar?
It is a deformed round steel bar and has a diameter of 12mm.
What is the unite weight of steel bars?
unit wt of reinforcement bar can be obtained in kg/ meter by d*d/162.162 where d is the dia of bar The formula is based on the density of rebar 490 lb/cft
What is extreme steel bar?
Extreme Steel bar is known as re-bar ( Reinforcing Bar), with two longitudinal and transverse ribs on the diameter of Bar.
What is TMT Re-Bars?
Thermo mechanical tempered Reinforcing bar or Structural steel
Is re-bar and reinforcement bar is same?
Yes.A rebar, or reinforcing bar, is a common steel bar, and is commonly used in reinforced concrete and reinforced masonry structures. It is usually formed from carbon steel, and is given ridges for better mechanical anchoring into the concrete. It can also be described as reinforcement or reinforcing steel. In Australia, it is colloquially known as reo.To know more about rebar visithttp://en.wikipedia.org/wiki/Rebarhttp://www.rgsrebar.com
Why steel is called rebar?
It's simply hardened steel that's been cast in long rods. It's used as reinforcing when pouring concrete to increase the strwength - especially in road construction or building foundations.
What is the meaning of steel re bar?
Rebar is an informal term for steel "reinforcing bar". These are steel bars that are placed within the structure before the wet concrete is placed. Steel reinforcement is necessary for almost all structural concrete because concrete has virtually no tensile or shear strength. The rebar provides almost all of the resistance to tension and shear within the structure.
What does deformed steel bar mean?
Deformed steel bar is more commonly known as reinforcing bar, or rebar. These steel bars are imbedded in concrete to provide tensile strength. Smooth bars are run through rollers which "deform" the bar thereby adding ribs. The ribs provide a mechanical bond between the steel bars and the surrounding concrete.
What is the diameter of a no 5 reinforcing bar?
5/8"
Is melting a candy bar a chemical change?
Melting a candy bar is a physical change because it is just changing form, not changing the chemical makeup. (If it isn't making a new material, it is not a chemical change)
What is 500w steel bar?
500W in steel bar means this steel yields 500MPa strength
What is 500W in steel bar?
500W in steel bar means this steel yields 500MPa strength
Is cutting a bar of sodium metal with a knife a chemical change?
Yes, cutting a bar of sodium metal with a knife is a physical change, not a chemical change. The chemical composition of the sodium metal remains the same before and after cutting. The change is only in the physical state of the metal.
Is melting an ice cream bar chemical or physical?
Melting an ice cream bar is a physical change because it involves a phase transition from solid to liquid without changing the chemical composition of the ice cream.
