A pedestal is a compressive structural member which is constructed between the footing and column. It is used to transfer the uniform load into the footing.
The shape of the pedestal can be square, octagonal, and circularr.
The pedestal is a compression member that has the length to least lateral dimension ratio is less than 3.
It is used where column load is extremely high, and we needed more depth of footing around column edge to transmit the load and stop failure of footing. We construct a pedestal to transfer load safely from column to footing.
The pedestal is normally utilized in steel structures or RCC structures where the column load is extremely high.
In ancient times it is used to provide support for statues. You can see the statue pedestal in the above figure.
Construction Details of Concrete Pedestal:
As discussed above, pedestals are provided above the footings. For small load-carrying columns, the pedestals are designed without any reinforcement and with a height less than three times its width. Normally hollow concrete blocks are utilized and the hollow place is filled with concrete. But this is only restricted to small load ranges.
In any case, on account of the large load on columns, the construction and design of pedestals are similar to reinforced concrete columns for primary loads. Reinforcement is also given for the pedestals but the quantity of reinforcement is 0.15 percent of its cross-sectional area. Likewise, if the pedestal height is more than 3 times its width then also, vertical reinforcement, ties, and dowels should be provided. The mortar utilized for the pedestal is similar to the mortar used for the concrete columns.
Uses of Concrete Pedestal:
- Pedestal avoid contact between foundation and column.
- It provides support for the thinner foundation
- It distributes uniform load to the footing.
- Sometimes it is constructed only for aesthetic purposes.