Steel is an alloy of iron and carbon containing less than 2% carbon and 1% manganese and small amounts of silicon, phosphorus, sulphur and oxygen. Steel is the world’s most important engineering and construction material. Some general points are the grade of the steel depending on yield strength of the steel, yield strength is considered as characteristics strength (fy) and presented as N/mm2,generally steel is available in the market from 8mm to 32mm .Generally they are two types of steel bars available in the Market that are mild steel and another one is deformed bars.
Mild steel is a plain surface it is used for tensile stress of RCC(Reinforced cement concrete) slam beams etc.. In reinforced cement concrete work. This steel bar are plain in surface and are round sections of diameter from 6 to 50 mm but we use 8mm to 32mm in constructions. These roads are manufactured in long length and can be cut quickly and be bent easily without damage. Mild steel consists of iron alloyed with les than 0.3percent carbon, most commonly between 0.1to 0.25 percent due to low strength these bars are seldom used here for denotes iron and 250 denotes yield of strength in mega pascal
Deformed steel bars are roads of steel provided with lugs, ribs or deformation on the surface of bar, these bar minimize slipping in concrete and increases the bond between the two materials. These bars have more tensile stresses than that of mild steel plain bars. The advantage of deformed steel bars are it can be used without end hooks. The deformation should be spaced along the bar and substantially uniform distances. Cold twisted deformed (ribbed or tor Steel Bars)bars are recommended as best quality steel bars for constructions work by structural engineer.
