Presentation for Column

3. Types of Column
Long Column or Slender
Short Column

4. Long column
Long column is that in
which the effective length
to least lateral dimension
ratio is grater than 12. i.e.
ratio R>12

5. Short column
Short column is that in
which the effective
length to the least
lateral dimension ratio
is less than 12. i.e. ratio
R<12

6. What is effective length?
For rectangular column
If
𝑳𝒆
𝒃
>12 then, it is long column
If
𝑳𝒆
𝒃
<12 then, it is short column

7. How to find out effective length?
For rectangular column
If
𝑳𝒆
𝒃
>12 then, it is long column
If
𝑳𝒆
𝒃
<12 then, it is short column

8. Classification on the Basis of Shape:
Square section.
Rectangular section.
Circular section.
L-section.
T-section.
Fig.1 Classification on the Basisof Shape

9. ii.Classification on the Basis of Reinforcement:
 Tied Columns:
These columns have the bars braced or tied at close intervals by close loops
called ties.


10. Spiral Columns:
These columns have the bars and the core concrete wrapped with a closely
spaced helix.
Fig.2(b) Classification on the Basis of Reinforcement

11. Composite Columns:
These columns consists of a structural steel or cast iron column
encased in concrete reinforced with both longitudinal and
transverse reinforcements.

12. Pipe Columns or Concrete Filled Steel Tubes:
These columns are circular, rectangular or square hollow sections filled with concrete without any
additional reinforcement.

13. Clear Cover
The clear cover is the distance between the exposed concrete surface (without plaster and other
finishes) to the nearest surface of the reinforcing bar Look into the following image for more detail.
Minimum distances 3” Clear cover below soil any structure
Minimum distances 1.5” Clear cover above soil any structure

14. Steel Column
Standard Structural Steel Sections

15. Build-up Column Sections

16. ADVANTAGES OF STEEL COLUMN
High Strength : This means that the weight of
column that made of steel will be small.
Uniformity: Properties of steel do not change in
any portion of Column.
Elasticity : Steel follows Hook’s Law very
accurately.

17. ADVANTAGES OF STEEL COLUMN
Ductility : Steel can withstand extensive
deformation without failure under high tensile
stresses
Toughness : Steel has both strength and ductility

18. DISADVANTAGE OF STEEL COLUMN
The use of steel columns is very economical because of
their high strength and slenderness of a compressive
column is increased, its danger of buckling increases
The strength of structural steel member can be reduced
if this member is subjected to cyclic loading.
Under certain conditions steel may lose its ductility ,
and brittle fracture may occur at places of stress
concentration.

19. Construction process

20. Detailing

21. Why column is important???
Columns carry the load of structure and
hence they are critical. It is important to
align them for verticality so that load is
transmitted properly. The column shuttering
should be strong enough to take the pressure
of fresh concrete and remain in position
during concreting.

22. THANKYOU