Most Important Point In This Article
What Is Column?
A compression member, i.e., column, is an important element of every reinforced concrete structure. These are used to transfer a load of superstructure to the foundation safely.
Mainly columns, struts, and pedestals are used as compression members in buildings, bridges, supporting systems of tanks, factories, and many more such structures.
A column is defined as a vertical compression member who is mainly subjected to the effective length and axial loads of which exceeds three times its least lateral dimension.
The compression member whose effective length is less than three times its least lateral dimension is called Pedestal
The compression member who is inclined or horizontal and is subjected to axial loads is called Strut. Struts are used in trusses.
The function of columns is to transfer the load of the structure vertically downwards to transfer it to a foundation. Apart from the wall performs the following functions also:
- It encloses building areas into different compartments and provides privacy.
- It provides safety from burglary and insects.
- It keeps the building warm in cools in summer and winter.
Also, read: What is CBR Test in Civil
Classification of Columns
A columns are classified based on different criteria such as:
- Shapes of Cross-Section
- Material of Construction
- Types of Loading
- Slenderness Ratio
- Types of Lateral Reinforcement
Shapes of Cross-Section
- Square
- Rectangular
- Circular
- Pentagonal
- Hexagonal
- Octagonal
- T-Shape or L-Shape etc.
Material of Construction
Types of Loading
- Axially Loaded Column
- Eccentrically Loaded Column
Slenderness Ratio
- Long Column
- Short Column
- Intermediate Column
What Is Short Column?
When this ratio of effective length to the least lateral dimensions of this column is less than 12, then it is knowns a short column.
(or)
When this ratio of effective length to the least radius of gyration is less than 45, then it is called a short column.When the length of the column is less as compared to its c/s dimension, it is called the Short column.
Short Column
A short column is the one whose ratio of effective length to its least lateral dimension is less than or equal to 12. Then it is termed as a short column.
lef / b ≤ 12
lef = effective length
b = least lateral dimension of column
What Is Intermediate Column? | Intermediate Column
Column is Intermediate
30d > L > 4d
and
100 > Le / r min > 30or Critical slenderness ratio.
Also, read: What Is Guniting, Set Guniting Systems , Advantage, Disadvantage
What Is Long Column? | Long Column
A long or slender column is the one whose ratio of effective length to its least lateral dimension is not less than 12. Then it is termed as a long column.
lef / b ≤ 12
lef = effective length
b = least lateral dimension of column
Long Column.
When this ratio of effective length to the least radius of gyration is greater than 45, then it is called a long column.
A long column is subjected to a bending moment in addition to direct compressive stress. The load-carrying capacity of a long column is less than a short column.
The load-carrying capacity of a long column depends upon slenderness ratio (slenderness ratio increases then the capacity of the column decreases)
Also, read: Difference Between Lap Length and Development Length
Difference Between Short Column and Long Column
| Sr.No. | Long Column | Short Column |
| 1 | Long column is considered to be long if the ratio of effective length of column to its least lateral dimension is greater than 12. | Short column is considered to be short if the ratio of effective length to its least lateral dimension is less than or equal to 12. |
| 2 | Long column is weaker than a short column and generally, it is not preferred. | The short column is stronger than a long column and it is highly preferable. |
| 3 | Long column, whose lateral dimension is very small when compared to its length (or height), is called as long column. | Short column, whose lateral dimension is very large when compared to its length (or height), is called a short column. |
| 4 | It is generally fails by buckling. | It generally fails by crushing. |
| 5 | The slenderness ratio is greater than 45. | The slenderness ratio is less than 45. |
| 6 | As the height of column increases the load carrying capacity is less. | As the height of the column decreases the load-carrying capacity is more. |
| 7 | Long Column Radius of gyration is less. | Short column radius of gyration is more. |
| 8 | Load carrying capacity is less. | Load-carrying capacity is more. |
| 9 | Long column is subjected to buckling stress | The short column is subjected to compressive stress. |
| 10 | Long and slender columns buckle easily. | The buckling tendency is very low. |
| 11 | The ratio of effective length of a long column to its least radius of gyration is greater than 40. | The ratio of the effective length of a short column to its least radius of gyration is less than or equal to 40. |
| 12 | The failure of the short column is by crushing. | The column generally fails in buckling. |
Also, read: What Is Lap Length | Lap Length of Column | Lap Length of Slab | Lap Length of Beam
Types of Lateral Reinforcement
- A column with Lateral Ties.
- A column with Helical Ties.
Also, read: Difference Between Footing and Foundation | What is Footing and Foundation
Failure Mode of Column
- A column can fail in one of three condition.
- Compression failure of concrete or steel reinforcement.
- Buckling.
- Combination of compression and buckling failure.
- Compression failure is likely to occur with columns that are short and stocky.
- Buckling is probable with a column which is long and slender.
Difference Between Long Column and Short Column
The column, whose lateral dimension is very small when compared to its length (or height), is called as long column. The column, whose lateral dimension is very large when compared to its length (or height), is called as short column. It is generally fails by buckling.
Lateral Dimension of Column
A column is defined as a compression member, the effective length of which exceeds three times the least lateral dimension. Compression members whose lengths do not exceed three times the least lateral dimension, may be made of plain concrete.
What Is Difference Between Long Column and Short Column?
The column, whose lateral dimension is very small when compared to its length (or height), is called as long column. The column, whose lateral dimension is very large when compared to its length (or height), is called a short column.
Slender Column
Slender columns can be defined as columns with small cross sections compared to their lengths. Generally, slender columns have lower strength when compared to short columns, for a constant cross section, increasing the length causes a reduction in the strength. The behaviour of slender column.
Slenderness Ratio of Short Column
If slenderness ratio is less than 12, it is called as short column, if SR is greater than 12, it is long column.
Slenderness Ratio of Long Column
A long or slender column is the one whose ratio of effective length to its least lateral dimension is not less than 12. Then it is termed as a long column.
Short and Long Column
Short columns have a large lateral dimension as compared to its height. Long columns have a small lateral dimension as compared to its height. The short column is stronger than a long column and it is highly preferable. Long column is weaker than a short column and generally, it is not preferred.
Like this post? Share it with your friends!
Suggested Read –
- What is Plum Concrete | Application | Mix Design | Methodology
- What Is Injection Grouting | Types of Injection Grouting | Different Types of Grouting Materials
- Detail of Beam Connection | Simple Framing Connection | Semi-Rigid Framing Connection | Rigid Frame Connection
- Mortar Vs Grout | What Is Motor and Grout | Types of Motor and Grout | Difference Between Mortar and Grout
- What Is Hempcrete | Hempcrete Blocks | Advantages & Disadvantages of Hempcrete Blocks | Applications of Hempcrete
Hey There. I discovered your weblog the use of msn. That is a
very well written article. I will be sure to bookmark it and return to learn extra of
youyr useful info. Thanks for the post. I’ll certainly comeback.
What is Timber, Classification and Conversion of Timber
Thanks for comment
More Detail for Go this link: https://civiljungle.com/difference-between-timber-and-wood/