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Footing Design For Moment

Mubeen Abid

By Mubeen Abid,
in Concrete Design

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Mubeen Abid Newbie

Mubeen Abid

Posted
Posted

Dear All

 

As salam alaikum,

 

In my case I have a footing for neck column(This neck column is upto tie beam level only), The tie beam tied to this column is supporting a FLOATING COLUMN. FLOATING COLUMN is resting on the edge of the cantilever of tiebeam.

 

I want to know what moments  shall I consider for footing design, shall i take the column bottom moments or shall i take column top moments which is from cantilever tie beam.

 

Kindly provide me your valuable suggestions.

 

For your referrence kindly find attached footing & tie beam layout.Structure.dwg

fdn layout.pdf

tie beam layout.pdf

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UmarMakhzumi Enthusiast

UmarMakhzumi

Posted
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I want to know what moments  shall I consider for footing design, shall i take the column bottom moments or shall i take column top moments which is from cantilever tie beam.

 

 

Mubeen,

 

It depends on how you model. Here is what I would recommend:

Connection between proposed column(at tie-beam level) and cantilever beam should be moment connection. Model that way, apply your loads, get the final reactions at the foundation level and design your foundation for that.

 

Other things that you should look at is:

1) Is your building in a seismic zone? If it is then your column from tie-beam level should not be part of lateral load resisting system. However, it should be able to deform with the structure for the given lateral load.

2) Check your cantilever beam for one way shear and serviceability.

3) Alternate solutions like Hilti in rebar in the foundation below and have columns start from there instead of cantilevering it.

4) What kind of contractor would be constructing this? Do you think construction would go a reasonable job with your design?

5) Solution should always look good on paper. What you have provided looks complicated.

 

Thanks.

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