[REQUEST] How to design mat foundation resisting 3 columns for Tower

[Munykong]

Dear everyone:

Please help me I do not know how to design mat foundation resisting 3 or 4 columns for Self support tower by manual.
Could anybody give me some idea or docs?
:dash2:

[Devil_Red]

1) Are your columns in grid ? or randomly placed?
2) And if the loadings of each column is relatively similar?

Manual calculations is easier if both your answer to above are 'yes'.
Else, your have to have considerable understanding about flat slab, As the mat foundation is somewhat similar to flat slab, concept-wise.

Let me pass you some tips for the thickness estimations.
You have to determine a size which pass the punching shear for all the columns (presumably you have the same thickness through out).

[chigozie]

Could you please up-load screen shots and include details in your brief?
Regards
Teddy

[visu]

Munykong,

Are you meaning support of the electric tower, which has 3 legs or 4 legs?
Please describe more about your question, or as commented earlier upload your drawings to get good response.

Regards,

[fsalmario]

What do you mean by "manual?"

I've design several mat foundation for telecommunication tower, 3 legs, 4 legs etc.
Assuming that the centroid of all tower legs coincide with the centroid of the mat foundation, it will be economical to provide relief hole in the middle. This will avoid excessive stress at middle portion.

However, you need a sfotware to anylyze this situation.

[allagui10]

Hi,
you need a software to design..
we can (strip mrthod) use a concentrated load applied to beam on elastic support and do a lot of combinations..
and we use interpolations of these combinations..in two ways..

[Munykong]

Dear all of you:

I mean that I want to analyze and design Foundation (mat) of telecommunication tower (self -supporting tower) ,but mostly calculation with finite element so that I do not know this and I am finishing my study in Cambodia, and all so difficult to look for book inherent.Therefore which software I can use to fit my knowledge

[vsa2010]

Munykong,

I've not designed telecommunication tower, but if you know the reactions(axial force, biaxial moments, shear force) of each leg, perhaps you can try "GS.AFES" to design your mat foundation.

You can find GS.AFES 3.0:

Code:

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Hope it's helpful to you.

ps:If you need to configure piles to support your mat foundation, it also has this feature.

[chigozie]

i do not think that your structure is a complex, one as such, it could as well be designed manually. Remember to include your loadings (axial, shear, moments etc -if you had alreay analyzed it) or include screen shots of your structure and your loadings (if you had not already analyzed it), the soil properties, the type of pile that you are using and all the relevant details. You can also use RISA footing, L-pile, All-piles or any other foundation software to design.
Regards
Teddy

[fsalmario]

I think most of structural software analysis can do the trick. But check thye software's limitation.

I've done similar problem, and I used staad for its analysis.