Column And Types Of Column

Introduction

In this article we are discussing the column and types of column. Column is a basic building component which is working a medium to transfer load from one member to another. Also, column carry different loads with different situation and so many things about column, we are discussing in the article.

Ø What is Column?

·A column is defined as a vertical building component which acts as a medium to carry or transferred load from slab and beam to footing or foundation and then footing transferred load to the hard strata.

·After foundation column is constructed in framed structure.

·Column is the middle member which is transferred load from superstructure to the foundation.

· It is a vertical member which supports structure very well from top of foundation up to slab of structure.

· The vertical member column has effective length which is greater than 3 times the least lateral dimension of column.

· Column can be constructed of different materials like stone, block, bricks, concrete, steel etc.

 

Ø  Why Columns Provide In Structure?

·  It plays an important role as component of building, it carries axial load in compression, and if it fails the whole structure can be collapsed.

· Bending is caused due to horizontal forces like snow loads, wind load and other horizontal forces which are acting on structure, to minimize and prevent bending in structure, column is provided.

· Settlement of structure is prevented by the column.

 

Ø  Types Of Column

According to different conditions, their used and many factors the column are classified into following types, 

A.    Based on the shaped

B.     Based on the type of reinforcement

C.     Based on the type of loading

D.    Based on the slenderness ratio

E.     Based on the construction materials

 

1.      Based On The Shaped

Following are the types of column based on the shaped

1.      Rectangular Or Square Column

2.      Circular column

3.      L Type Column

4.      T type column

5.      V type column

6.      Hexagonal column

1.      Rectangular Or Square Column

ü This column mostly used in building construction, if the room size is square or rectangular, it is more suitable.

ü These columns are easy to construct as compare to the circular column.

ü It is an economical construction.

                          

                                        

                 

 

2.      Circular Column

ü The circular columns are mostly used for aesthetic purposes of buildings’ to make elevation attractive.

ü For the construction of circular column, more than 4 longitudinal steel bars required.

ü The circular columns are more bending resistive than the square or circular columns.

ü These columns have good resistance against deflection, so they are mostly used in bridge pillars.

                         

 

3.      L Type Column

ü The L types of columns have similar characteristics of rectangular and square columns.

ü  Generally, they are used in frame structures at the corners of the boundary wall.

ü  They are used to resisting both axial compression and biaxial bending of corners.

 

 

4.      T Type Column

ü  According to requirement of the structure, T type of column is used.

ü  Mostly used in the construction of bridge.

 

5.      V Type Column

ü  In the trapezoidal room or structure, the V type of column is used.

ü It requires more quantity of materials as compared to other.

 

6.      Hexagonal column

ü  It is generally used in elevation so that make good pictorial view.

ü  It is used at verandahs, auditoriums, and cinema halls, etc.

 

 

 

 

B.     Based on the type of reinforcement

According to type of reinforcement used, the reinforcement column has following type,

1.      Tied column

2.      Spiral column

3.      Composite column

 

 

1.      Tied Column

ü  It is most commonly used column in the building constructions, in which longitudinal bars of column are tied together by ties.

 

2.      Spiral Column

ü  The main longitudinal reinforcement bars in column are tied with the spirals.

ü  When high strength and high ductility required this column is used.

ü  Spiral columns support the transverse direction and help to prevent the column from barreling.

 

 

 

3.      Composite Column

ü In the composite column, longitudinal reinforcement is in the form of structural steel section pipe, the pipe can be with or without longitudinal bars.

ü  They are mostly used in truss structure, to avoid corrosion of steel.

 

 

 

C.    Based On The Type Of Loading

According to type of loading, the columns have following type,

1.      Axially loaded column

2.      Uniaxial eccentrically loaded column

3.      Biaxial eccentrically loaded column

 

1.      Axially Loaded Column

ü  In axially loaded column, the vertical axial load act on the centroidal axis of the column.

ü  The column is rarely used in construction.

 

2.      Uniaxial Eccentrically Loaded Column

ü  Uniaxial eccentrically loaded column is the column in which the axis of vertical load does not coincide on the centroidal axis of column i.e. centre of gravity of column, but it is coincided with the X or Y axis of the column cross section.

 

3.      Biaxial Eccentrically Loaded Column

ü  Biaxial eccentrically loaded column is the column in which the axis of vertical load does not act at the center of gravity of column and X or Y axis of the column’s cross section.

 

 

D.    Based On The Slenderness Ratio

According to slenderness ratio (ratio of effective length to the least lateral dimension of column), columns have following type,

1.      Short column

2.      Long column

 

 

 

1.      Short Column

ü  The short column is said to be when the slenderness ratio of column is less than 12.

ü  Due to crushing short column fails.

 

 

2.      Long Column

ü  The long column is said to be when the slenderness ratio of column is greater than 12.

ü  Due to bending or buckling, long column fails.

 

E.     Based On the Construction Materials

According to construction materials, the columns have following types,

1.      Reinforced concrete column

2.      Composite column

3.      Timber Column

4.      Brick column

5.      Block column

6.      Stone column

 

1.      Reinforced Concrete Column

ü  Reinforced concrete column is made up of reinforcement and concrete.

ü  Concrete is strong in compression but weak in tension, and reinforcement is strong in tension.

ü  Reinforcement column is commonly used in constructions.

 

2.      Composite Column

ü  By using various combinations of structural steel and concrete, composite columns are constructed.

ü  The combinations of structural steel and concrete make columns stiff, cost-effective, more ductile.

ü  The composite columns are great fire and corrosion resistance.

 

3.      Timber Column

ü  The column which is made by timber wood is called timber column.

ü  In previous century, they were popular material as columns for building construction.

ü  With proper treatment, the timber columns can make strong and durable for construction.

 

4.      Brick Column

ü  For load bearing structure brick columns are used.

ü  They are increasing the stability of masonry structure.

ü  They can be circular, rectangular, square or elliptical.

ü  They make aesthetic appearance of structure.

 

 

 

5.      Block Column

ü  AAC block or cement concrete block are used for the block column.

ü  Advantage of the column is it is light as compared to concrete column.

 

6.       Stone Column

ü  By using stones and rubble materials, stone column can construct.

ü  The main and important use of column to make aesthetic view of structure.