Following are the standard shapes in which the rolled steel sections are available in the market:
(1) Angle sections
(2) Channel sections
(3) Corrugated sheets
(4) Expanded metal
(8) Ribbed (HYSD) bars
(9) Round bars
(10) Square bars
(11) Flat bars
(12) Ribbed mild steel bars
(13) Thermo-Mechanically Treated bars (TMT bars)
(14) Cold Twisted Deformed bars (CTD bars)
(15) Welded Wire Fabrics (WWF)
(1) Angle sections: The angle sections may be of equal legs or unequal legs The angle sections are extensively used in the structural steelwork especially in the in the construction of steel roof trusses and filler joist floors.
(2) Channel sections: The channel sections consist of a web with two equal flanges The Bureau of Indian Standards has classified channel sections as junior channel, light channel and medium channel and accordingly they are designated as I.S.J.C., I.S.L.C. and I.S.M.C. respectively.
(3) Corrugated sheets: These are formed by passing steel sheets through grooves. These grooves bend and press steel sheets and corrugations are formed on the sheets. These corrugated sheets are usually galvanized and they are referred to as the galvanized iron sheets or G.I. sheets. These sheets are widely used for roof covering.
(4) Expanded metal: This form of steel is available in different shapes and size. It is prepared from sheets of mild steel which are machine cut and drawn out or expanded. A diamond mesh appearance is thus formed throughout the whole area of the sheet. The expanded metal is widely used for reinforcing concrete in foundations, roads, floors, bridges, etc. It is also used as lathing material and partition.
(5) T-sections: The shape of this section is like that of letter T and it consists of flange and web,
(6) I-sections: These are popularly known as the roiled steel joists or beams. It consists of two flanges connected by a web. The Bureau of Indian Standards has classified T-sections into junior beams, light beams, medium beams, wide-flange beams and heavy beams and they are accordingly designated as I.S.J.B., I.S.L S., I.S.M.B., LS.W.B. And respectively.
(7) Plates: The plate sections of steel are available in different sizes with thickness varying from 5 mm to 50 mm. The corresponding weights per square metre are 392 N and 3925 N respectively. They are used mainly for the following purposes in the structural steelwork:
(ii) To connect steel beams for extension of the length;
(ii) To serve as tension members of steel roof truss; and
(ii) To form built-up sections of steel.
(8) Ribbed (HYSD) bars: Described in separate topics
(9) Round bars: These are available in circular cross-sections with diameters varying from 5 mm to 250 mm. They are widely used as reinforcement in concert structures, construction of steel grillwork, etc. The commonly used cross-sections have diameters varying from Ã mm to 25 mm with the corresponding weights per meter length as 1.50 N and 35 N respectively.
(10) Square bars: These are available in square cross-section with sides varying from 5 mm to 250 mm. They are widely used in the construction of steel grillwork, for windows, gates, etc. The commonly used cross-sections have sides varying from 5 mm to 25 mm with corresponding weights per metre length as 2 N and 49 N respectively.
(11) Flat bars: These are available in suitable widths varying from 10 mm to 400 mm with thickness varying from 3 mm to 40 mm. They are widely used in the construction of steel grillwork for windows and gates.
(12) Ribbed Mild Steel Bars: These are the hot rolled mild steel bars but during rolling steel rods. Ribs are produced on them. These ribs increase the bond strength of the bars. Such ribbed mild steel bars are not recommended in the code but are available in the market. They look like high strength ribbed bars, but the allowable stresses in these ribbed mild steel bars are much lower than HYSD bars. These bars should not be used in R.C.C. work.
(13) Thermo-mechanically treated bars (TMT bars): Described in separate topics
(14) Cold Twisted Deformed bars (CTD bars): Described in separate topics
(15) Welded Wire Fabrics (WWF): Welded wire fabric is fabricated from a series of wires arranged at right angles to each other and electrically welded at all intersections. It is made from medium tensile steel drawn out from higher diameter mild steel bars. It is much stronger than mild steel and are available in different width rolls. It is mostly used for floor slabs on well-compacted ground. Heavier fabric, supplied mainly in flat sheets, is often used in walls and for the primary reinforcement in structural floor slabs. It is also used in road and runway pavements, box culverts and small canal linings.
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