Base Plate work point
Base Plate work point
(OP)
Hi,
For braced frames, where should the workpoint (WP) at base plate be? CL of column and CL of brace intersection at top of baseplate or CL of column and CL of brace intersecting at bottom of baseplate? I have seen it done both ways. What are the differences between these two? If UFM is used, forces for the gusset plate to column and base plate connection will change with respect to WP.
Contractor likes to have WP at top of base plate. Is there any additional consideration for the design other than the change in connection forces between gusset plate and column/base plate if workpoint is kept at top of base plate?
Thanks
For braced frames, where should the workpoint (WP) at base plate be? CL of column and CL of brace intersection at top of baseplate or CL of column and CL of brace intersecting at bottom of baseplate? I have seen it done both ways. What are the differences between these two? If UFM is used, forces for the gusset plate to column and base plate connection will change with respect to WP.
Contractor likes to have WP at top of base plate. Is there any additional consideration for the design other than the change in connection forces between gusset plate and column/base plate if workpoint is kept at top of base plate?
Thanks






RE: Base Plate work point
RE: Base Plate work point
RE: Base Plate work point
RE: Base Plate work point
RE: Base Plate work point
- Agree with Once that, in many instances, you want the work point to coincide with the center of action of that which is assumed to provide the shear resistance.
- Agree that the thickness of the base plate makes little difference.
- For the common case where shear is transferred through the anchor bolts, particularly via a weld washer, I believe that there is some technical merit to using the top of base plate as Jayrod and your contractor suggest. Ideally, you'd like your column and gusset plate welds to see only tension and shear forces, no moments. By definition, you've got a little moment in the welds with the work point at the bottom of the base plate. This is a slight thing, of course.
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.
RE: Base Plate work point
Shear lug is being used to resist the shear. Irrespective of the WP position (whether at the top or bottom of baseplate), the shear lug design will be the same right?
RE: Base Plate work point
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.
RE: Base Plate work point
RE: Base Plate work point
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.
RE: Base Plate work point
Anyways, shear lug size will not change with change in WP. This is what I am trying to get to.
RE: Base Plate work point
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.