What Are Stub Columns?

A stub column is defined as a type of column whose length is small and sufficient to prevent the column failure and long enough to contain the residual stress pattern that would exist in the column. It is not directly connected to the footing or a column. 

What Are Stub Columns?

It is an additional member constructed over the beam or slab that would help increase the stiffness of the building and bring symmetrical load distribution. It is a redundant compression member.

As shown in the figure above, stub columns are constructed over a slab and act as a point load over the slab. 

Need For Stub Columns

1. Stub columns are introduced to bring symmetry in geometry and load distribution.
2. It is used to increase the aesthetic view of the building
3. It is introduced as an intermediate member between long-span rooms i.e. when the beam span increases, deflection increases. This can be reduced by introducing a stub column.
4. Stub columns are introduced to take unexpected extra loads coming over the building during the construction process.
5. It is used to increase the stiffness of the building.
6. A stub column helps safe load transfer from one beam to another.

Stub columns mainly lie over a beam and not on footing. This can create extra shear in the beam, which is nonacceptable. So, we need to design the beam for an increased cross-section. This makes the stub column an uneconomical option in certain circumstances.

Also Read:
What is a Floating Column?
What are Inclined Columns?