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Concrete Mix Ratio One way and two way slab

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Cantilever footing can be described as a combination footing where the cantilever action balances the eccentricity caused by the column load.

The combined feet combines the actions of the strap beam, inner column foundation and strap beam.

This type of footing is called cantilever footing because of the cantilever nation in the strap beam.

What is the Canlitlever footing foundation and what does it do?

It is not possible to always build the column in the middle of an isolated footing. Footing cannot be constructed in other land if the building extends beyond the boundary. In these cases, the column must be placed at the edge.

  • Loading the footing near the edge results in rotation at its center, or in other words eccentric loading increases soil stress at the column location.
  • This could cause soil to settle or bear the consequences of exceeding its bearing capacity. For more failure mechanisms, you can refer to the shallow Foundation Failure article.
  • To balance the stress concentration at the footing's edge, we attach a beam to the electrically-loaded footing.
  • Due to rotation caused by the load eccentric, there is an upward movement in the beam at support. It's like a cantilever.
  • These types of shallow Foundations are known as cantilever feetings. These foundations also fall under the spreadfooting.

Read: flat roof material types

Design for Cantilever Footing

The strap footing design has a cantilever footing.

We must also consider the bending stresses caused by vertical loads in the ultimate state.

In the last section of the article Strapfooting, we discuss the steps to follow during design. For more information or to see examples of work, you can refer to this article.

Read: how to measure rebar diameter

Important aspects of Cantilever Footing

Why do we need: Are we required to always connect an electrically loaded footing to an internal column with a strap beam? No. You can build footings with eccentricity. This can be done with footings. Designers must follow certain guidelines.

A New Column on the Ground Floor Can Avoid Load Eccentricity: Some modifications can be made in order to eliminate the eccentricity of your footing. You can shift the column towards the center of your footing, and then construct a floating column at the boundary.

Cantilever The Beam: To extend the building, we can build the column in the middle of the footing. We can also cantilever each beam floor-to-floor toward the boundary.
Construction: The foundation for the cantilever footing shall be constructed with as much soil as possible. The soil investigation report will recommend ground improvement. Also, consider the soil type as having large soils can cause problems in design and construction.

Read: one way and two way slab

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