WR1

How do I know what is your confusion without you writing it down for me?

I dont think code dictates that but yes common sense sure does. I wouldnt design foundation unless from some source I have the bearing capacity information. Even if it is preliminary design and you put a note that "the foundations have been designed assuming.....capacity", you should do some research of nearyby buildings. You cant just guess, i think.

First off, is your Limcon cracked or purchases? If cracked, there are certain variables in the software that are "FIXED". They do not change if you change values. So beware!

Depends if the sheet is correct? Does the sheet take into account moments?

Really? Moment frame type has nothing to do with location except some limitations in codes. Can't you have special moment frame in Zone 2? Yes, you can! Type depends on the ductility and framing of building system. Do you think it has enough ductility? If yes then it could be special even in Zone 0. But obviously it will cost more to provide that ductility and detailing for zone 0. But generally speaking, you could design special frames in zone 2B or ordinary in higher zones, depends on the framing.

not true in all cases. uncontrolled internal temperature has the same effects like outside sun heat on the structure. There are usually documents stating weather station data. You should use mean yearly average highs and lows not daily. It also depends on approval authority. For example in Dubai, limit is 45m. Expansion joints are nice from structural point of view only. As a structural engineer, Id try my best to avoid them. Construction isnt that easy for expansion joints. What about water leakage? Except ground floor columns and walls that will have huge forces due to restrain (supports). This is my opinion. I don't think T+E should be added.

Known or unknow?

Yes, more bars less dia is better. Also check what is commercialy viable. There is commercial as well as health & safety aspect to it as well. For example using less bars of dia 40 reduce congestion and easy handling and placing but is it safe for workers to carry such huge bar? Accidents?

You could also use concrete society report no. 34 for plastic design of industry ground slabs.

Good point again. In such cases, you have to deal with the notorious huge nerve sapping temperature forces.

You are not getting the point. Have you referred to the codes? Aci or bs or whatever? An interior column with huge axial load multiplied by minimum e can produce huge moment even if the original moment from frame is 0.

2d analysis is never recommended with walls above. https://wiki.csiamerica.com/m/view-rendered-page.action?spaceKey=safe&title=Modeling+uplift+and+foundations+on+soil+supports

Hey man, hold on. Your building isnt symmetrical. Also the theres difference between axial stiffness of cols vs walls. This will effect z direction deflections from bottom to top stories. 2nd thing..safe..in safe deflections will be different than in etabs. This has been discussed no of times here and you can search.

If the building is regular as you said with same column sizes, axial shortening should be same provided loading and gemoetry all are same and symmetrical. Gravity deflection on same combination should be same at each level. And by deflection i mean z deflection not x.

10 under the root factored load in kN is the thickness required in mm (tried & tested here).

Decrease the distance between CR & CM. It will not eliminate 100% due to inherent torsion.

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In addition to above, to get an idea how point load is distributed, see PCI Handbook.

Answer is simple. Top columns have less axial load and more moment. That means more in the tension region of interaction diagram.

It does. Simply use 3d.

Expansion joints in superstructure are provided for lateral movements e.g. from wind/earthquake/temperature/geometry. No need in foundations as soil has sink down effect for temperature and earthquake and winds and geometry effects are above ground.

You need to size the slabs for long term deflections. Forget these tables.

It will still design for minimum eccentricity. Refer to ACI chapter 10 I think. You can turn it off (not recommended) if you want in ETABS design overwrites.

It depends on the ratio of local area vs total area. It also depends on the location and importance of localized stress area among other factors. This is engineering judgement beyond the number crunching drudgery. I cant provide this as I am not aware of the project details. You could refer to your seniors for this. And remember do not stop at this. There is always a solution no matter how hard the problem is. For example may be your geotech engineer might suggest a lesser soil stiffness value at this location which will help reduce the stresses. You might increase the local thickness to better distribute the pressure. You could optimize the load combinations or even the load path of superstructure not to have the concentration here. An important point here is if this is localized compression at corner then is it due to lateral loads? If yes then watchout for the reverse that is tension (blue color contours). This will be another whole new problem.

1. Depending on how much the value is exceeding you could increase thickness of the footing. 2. Soil improvement. 3. Reduce loads/stories.