Flat Plate Design - Column Strips For Shear Walls

[ahypek]

Is there anything in the ACI that specifically tells you how to deal with establishing column strips around a shear wall?

Throughout the years, aside from FEM, I've been taking the shortest span to the nearest column or wall from the nearest centerline of my shear wall to develop a column strip around it but this is just the way that I've learned this from engineers over the years. Occasionally I need to tweak it, depending on where I'm spotting my zero shear from FEM analysis. Is there anything that references exactly how to handle shear walls as columns for EFM or DDM?

 

[KootK]

I don't know of anything. I've seen it done as you've described predominantly. In many respects, walls are handled by envisioning them as though they were replaced by discrete columns located at each end of the wall,

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[calvinandhobbes10]

Never seen anything in ACI. Without FEM I don't know how we would handle the eccentric grids I've grown accustomed to getting. Use it to check moment and check deflection. This S how I've been taught.

For walls i usually ensure i have slab bars top and bottom at 12 maximum, perpendicular to the wall plane, and making sure I continue spacing these bars four to six feet past the wall corner, where it's most liable to see atypical stress concentrations. Away from the walls, where I have typical regular column grids, I economize reinforcing tightly.

 

[rapt]

Agree with Kootk.

Put a column at each end with a length of twice the wall width, centred 1 wall width back from the end of the wall and base the column strips on the spans to the ends of the wall from the columns either side. If the wall is very long, add extra columns between the ends so that the slab is basically continuously supported and will not affect the design either side. Then reinforce parallel to the wall as a middle strip, and perpendicular to the wall as normal column and middle strip.

 

[Retrograde]

I would love to find a good reference for setting up design strips where the columns do not follow any recognisable grid pattern. FEM is fine but it is nice to run some independent 2D strips to check critical deflections rather than just relying on the deflection multipliers that FEM packages use.

 

[slickdeals]

Attached is a sketch of what is being described above.

https://books.google.com/books?id=h...nepage&q=flat plate column strip wall&f=false