Bolts under compression (at a certain unbraced length)

[GalileoG]

Where can I find information on how to determine the compressive capacity of a bolt under a certain unbraced length? Say like an anchor rod prior to the placement of grout.

Well, since I'm asking, I'll pose another question: When I have a point load applied on an HSS wall, how can I determine that this load does not excessively bend/buckle the wall?

Thanks!

 

[jtx]

I'm not quite sure what you are asking in your first question. Usually an anchor rod undergoes tension and shear forces. Maybe some additional info so I know what you want to do with the anchor.

For your other question, AISC 13th ed chapter k covers connections to HSS walls. That should give you the info you are looking for

 

[Lion06]

I would not worry about your first question unless you have a very large gap between your baseplate and top of footing AND they are using leveling nuts instead of a leveling plate. The typical grout bed is 3/4" and the only load they would see is self-weight of the structure (they should definitely be grouting it before slabs are poured). Given those conditions, the loads are minimal and I wouldn't worry about it................... BUT, if you want to check, you can just use the column buckling equations from the AISC spec. You can also probably assume a fixed-fixed condition (because the embedment into the footing will minimize rotation and the double nutting on the baseplate will also minimize rotation. Check a column as fixed-fixed (with k=0.7) for the small length (usually on the order of 3/4" to 1 1/2") for only the self weight (excluding and slab load) and I doubt you'll have any problem.

 

[GalileoG]

Thank you for the informative responses.

StructuralEIT,

The bolts under compression is for a precast panel, where the unbraced length can be up to 6" inches, I used the example of an anchor rods without grout just because people are more familiar with a rod under compression in that application.

I will treat my bolt as a column, as per your suggestion. Thanks again.