The document discusses structural steel used in construction. It describes the different types of steel based on carbon content and their properties. It also discusses reinforcement steel and structural steel sections used in construction. The main types of reinforcement steel discussed are mild steel, medium tensile steel, and high yield strength deformed bars. The main types of structural steel sections described include rolled sections like angles, channels, I-sections, tubes, plates, as well as built-up sections. Light gauge steel sections made from thin steel sheets are also summarized.

1. STRUCTURAL
STEEL
WORK

2. STEEL
● Most popular and effective building material.
● Steel is an alloy made by combining iron and other elements, the
most common of these being carbon.
● wrought iron and cast iron
wrought iron - Carbon content: not greater than 0.15%
steel - Carbon content: 0.15% to 1.5%
cast iron - Carbon content :2% to 4%

3. Varieties of steel
● Based on carbon content
● Mild steel – 0.15 to 0.25%
● Medium carbon steel
- 0.25 to 0.6%
● High carbon steel - 0.6 to 1.5%
● Increase in carbon
content
● Increase strength
● Decrease ductility

4. MANUFACTURING PROCESS
● Hot rolling
Temperature above recrystallization by rolling hot steel
in semi solid state (900 to 12500).
● Cold rolling
Temperature below recrystallization rolling sheets from
sheets, plates or flats in rolling machines or by press breaking.

5. Mild Steel
● Carbon content – 0.25% (max)
● Sulphur – 0.055%
● Phosphorous - 0.055% ( I.S. 226: 1969)
● Dark bluish colour
● It is tough, elastic than cast iron and wrought iron.
● It is malleable and ductile.

6. Properties of Mild Steel
● Can be magnetized permanently.
● Readily welded, riveted and bolted.
● Easily hardened or tempered.
● Malleable and ductile.
● Specific gravity 7.8.
● Melting point – above 1400°C.

8. Uses of Mild Steel
● Used as steel reinforcements (mild steel round bars).
● Mild steel tubes are used in construction.
● Mild steel sheets are used for roof coverings.
● Used in manufacture of various tools, machinery and other
equipments.

10. Steel is used structurally in two ways
● Reinforcement steel
● Structural steel

11. Reinforcement Steel

12. Reinforcement Steel
● Concrete – weak in tension – strong in compression
● Steel – strong in tension
● Steel bars embedded in concrete – reinforcement
● Develops good bond with concrete .

13. Reinforcement Steel
● Concrete – weak in tension – strong in compression
● Steel – strong in tension
● Steel bars embedded in concrete – reinforcement
● Develops good bond with concrete .

14. Types of Reinforcement Bars

15. Mild steel and medium tensile
steel / Plain steel bars
● Round sections
● Mild steel / medium tensile steel /
plain steel bars
● Plain steel bars – 5mm to 32mm
● Designated as Fe250
● Yield strength – 250 N/mm2

16. High yield strength deformed
bars (HYSD)/ TOR steel
● Cold twisted deformed bars.
● Tor steel bars – longitudinal ribs in
the form of continuous helix.
● Develop high bond strength due to
interlocking with concrete.
● Mean diameters – 5mm to 40mm.
● Designated as Fe415, Fe500, Fe550.

17. Advantages of tor steel
● Good bonding capabilities
● High yield strength
● Saving in reinforcement cost
● Better structural properties
● Bars can be welded

18. STRUCTURAL STEEL
SECTIONS / MARKET
FORMS OF STEEL

19. STRUCTURAL STEEL SECTIONS:
● Angle sections
● Channel sections
● I-sections
● T-sections
● Flat sections
● Steel plates
● Corrugated sheets
● Round bars
● Square bars

20. Rolled steel bar section:
Indian Standard Round Bars (ISRO):
● Designated as ISRO 10 (round bars
having diameter 10mm)
● Available in diameter varying from
6mm to 25mm.

21. Indian Standard square bars
(ISSQ):
● Designated as ISSQ 10 (square bars
of size 10mm)
● Used for grillwork, handrails for
staircases etc.

22. Rolled Steel Plate Section ( ISPL):
● Designated as ISPL 500 x 5 (500mm
width and 5mm thickness)
● Used for construction of water tanks and
other storage structures, built up beams,
columns, base plate for foundations etc.

23. Rolled Standard Sheet Sections
(ISSH):
•Plates having thickness less than 5mm.
•Designated as ISSH 1800 x 600 x 4
(sheet having length 1800mm, breadth
600mm and thickness 4mm).
•Used for construction of boxes and
vehicle bodies.

24. Indian Standard Flats (ISF):
•Designated as ISF 10 x 3(flat of width
10mm and thickness 3 mm).
•Available in suitable widths varying
from 10mm to 400mm
•Thickness varying from 3mm to 40mm.
•Used for steel grillwork for windows
and gates.

25. Rolled Steel Tubes:
● Inner diameter varying from 15 to
150mm.
● Thickness varying from 2 to 5.4mm.
● Efficient structural sections for
formwork and trusses.

26. Rolled Steel Angle Sections
(ISA)
● Designated as ISA and width and
length of legs
● Available as
● Equal angle sections
● Two legs will be equal in length
● Available in sizes varying from
20mm x 20mm x 3mm to 200mm x
200mm x 25mm

27. Unequal angle sections
● Two legs will be unequal in length.
● Available in sizes varying from
30mm x 20mm x3mm x 3mm to
200mm x 150 mm x 18mm

28. Bulb angle sections
● Extensively used in structural steel
works like roof trusses, and as
connecting members for different
structures.

29. Rolled steel Tee sections:
● Resembles the alphabet T
● Consists of web and flange
● Designated by overall dimensions
and thickness.
● Available in sizes varying from
20mm x 20mm x 3mm to 150mm x
150mm x 10mm.
● Widely used as members of the steel
roof truss and form built – up
sections.

30. Rolled Steel Channel Sections:
● Consists of a web and two equal
flanges.
● Designated by height of web and
width of flange
● Available in sizes varying from
100mm x 45mm to 400mm x
100mm.
● Widely used for beams and columns.

31. The different types available are:
● Indian Standard Junior Channel (ISJC)
● Indian Standard Light Channel (ISLC)
● Indian Standard Medium Channels (ISMC)

32. Rolled Steel I – Sections
● Known as rolled steel joists or beams.
● Consists of two flanges connected by a
web.
● Designated of overall depth and width
of flange.
● Available in sizes varying from 75mm x
50mm to 600mm x210mm.

33. Different types are:
● Indian Standard junior beam (ISJB)
● Indian Standard Light Beam (ISLB)
● Indian Standard Medium Beam (ISMB)
● Indian Standard Wide Flange Beam (ISWB)
● Indian Standard Heavy Beam (ISHB)

34. Built –up sections:
● Composed of a combination of
available basic sections like plates,
angles, channels etc.
● For increased strength and stability
● Different sections are joined by
welding or riveting

36. Light gauge sections
● Made from steel sheets of uniform
thickness – process in cold state
● Coated with zinc or aluminium
● Thickness normally less than 2mm
● Yield stress ranging from 250MPa to
550 MPa.
● Normally have stiffening lips on
flanges
● Intermediate stiffeners in wide flanges
and webs

38. Advantages of light gauge sections
● Lightness
● High strength and stiffness
● Ease of fabrication and mass production
● Fast and easy erection and installation
● High strength to weight ratio
● Substantial elimination of delays due to weather
● Formwork not needed
● Uniform quality

40. THANK YOU
PALUVADI MUKUNDA PRIYA
18031AA058