settlement computation on a footing subjected to moments and axial load 1

[pelelo]

Engineers,

I posted this question in the geotechnical forum but did not get a response.

I was wondering if a structural engineer can provide any feedbacks about this. At the end, the structural engineering and geotechnical engineering overlap at some point.

I have a footing subjected to Moments in X and Y and axial load as well. As you may know, this is not a typical situation in which we are used to compute bearing capacity and settlement using only axial load.

Since in this case excentricity plays a role, I was wondering if anyone knows a reference that explain how to compute settlements when we have this situation.

There are many references that explain how to compute bearing capacities for excentric footings (computing a B' or beffective and L' or Leffective) and use these dimensions to compute bearing capacity.

But the question is how to compute settlement?, what would be the approach?, clearly Mx and MY will contrubute to additional settlements other than the one caused by the axial load.

If anyone knows any reference that could explain this, please share

Thanks.

 

[HTURKAK]

My points ,

- If you are looking for the foundation rotation , you may use the following formula, ( excerpt from FOUNDATION DESİGN ,by BOWLES )

- If you are looking for the settlement of corners of a footing , you may use Boussinesq approach to find the stresses at layers mid heights ,then calculate the settlement for each layer then sum up to find the total settlement prediciton.
You may look to the same book ( FOUNDATION DESİGN ,by BOWLES ) Section 5-4 SPECIAL LOADING CASES FOR BOUSSINESQ SOLUTIONS.

- If the problem is for the entire foundation of a building, in this case you should have problem with foundation design. The subject moment effects should be for wind or EQ and the settlement is calculated only for gravity loads ( DL + %of LL ) You should improve the foundation design to avoid moment effects.

P.S. I did not experience such a problem in my engineering life ..




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