Steel structure Steel sections joints

2. Introduction to Steel Structures:
Steel structures are assembly of structural steel shapes joined together by means of riveted, bolted or welded
connections.
In Steel construction, Steel is the main load carrying material to transfer the load within them and transfer load to
the ground.
Examples of structural steel shapes are I-beam, channel section, Tee section, angle section etc.

3. CONNECTIONS:
BOLTING RIVETING WELDING

4. In steel structures connections including the details are to be designed for expected forces.
Steel construction is being used for almost every type of structure including high-rise buildings, bridges,
industrial building, towers etc.
There are main two categories of steel structures:-
• Framework or Skeletal Systems • Shell Systems
Majority of concrete structures are cast-in-situ but in steel structures, we have to select out of those
available in the market.
Joints are monolithic in concrete structures whereas in steel structures special methods are required to join
individual members.
Steel concrete composite structures are also used in high rise buildings but we are only going to study about
steel structures in this paper.

5. Framework or Skeletal Systems
The main load carrying elements are one-dimensional or line elements (such as
beams, columns, etc.) forming two-dimensional or three-dimensional frames.
Examples are:-
• The frameworks of industrial buildings with their internal members such as crane
girders, platforms, etc.
• Highway and railways large span bridges.

6. FRAME STRUCTURES
Industrial building
Multi Storey building
Large halls
Domes
Towers
Poles
Trusses

7. SHELL SYSTEMS
The main load carrying elements in this category of structures are plates and
sheets.
Examples are:-
• Gas tanks for storage and distribution of gases.
• Tanks and reservoirs for storage of liquids.
• Bins and bunkers for storage of loose material.
• Special structures such as blast furnaces, air heaters, etc.
• Large diameter pipes
• All other plate and shell structures.

8. Large Diameter Pipe
Shell Structures

17. Temporary construction
• Steel structure is always preferred for
temporary construction.
• Army constructions during war are
mostly made out of structural steel.
• The structures may be disassembled
by opening few bolts, component parts
are carried to new places and the
structure is easily reassembled.

18. CREATIVITY

19. MERITS OF STEEL CONSTRUCTION:
1. Reliability
2. Industrial Behavior
3. Lesser construction time
4. High strength & Light weight nature
5. Uniformity, durability & performance
6. Elasticity
7. Ductility & warning before failure
8. Extra loads may be removed to prevent collapse
9. Additions to existing structures
10.Possible reuse steel scrap
11.Water tight & air tight
12.Long span structures

20. DEMERITS OF STEEL CONSTRUCTION:
1. High maintenance cost and more corrosion
2. Fire Proofing cost
3. Susceptibility to buckling
4. Higher initial cost/ less availability
5. Aesthetics

37. CONNECTIONS

49. ROOF TRUSS TO COLUMN JOINT