Anchor Reinforcement in RAM Connection

RE: Anchor Reinforcement in RAM Connection

Benhang Shi — Thu, 21 May 2020 00:34:05 GMT

Yes, that would help a lot. We have the same confusion here.

RE: Anchor Reinforcement in RAM Connection

Blake Austin — Fri, 17 Apr 2020 18:33:00 GMT

Yes, I believe that would help clear things up. It would be verrryyy cool if the dxf could show this reinforcement!!!

RE: Anchor Reinforcement in RAM Connection

Karl G — Fri, 07 Apr 2017 15:29:45 GMT

Jason, I reran the tests and now see consistent behavior among RAM Connection Standalone, RAM Connection for RAM Elements, and RAM Connection for RAM Structural System. I tested both single column base plates and gusset base plates. I have edited the original post accordingly. I am not sure what happened yesterday, but apologize for the confusion.

In summary:

Shear anchor reinforcement in the major direction increases shear capacity associated with the minor axis.
Shear anchor reinforcement in the minor direction increases shear capacity associated with the major axis.

Regarding your other points and the figure in ACI:

By "in the major direction," we mean parallel to the local 3 axis, which defines the major axis. V3 is minor axis shear and parallel to the local 3 axis.
By "in the minor direction," we mean parallel to the local 2 axis, which defines the minor axis. V2 is major axis shear and parallel to the local 2 axis.

If you interpret "in the _ direction" as above, then the RAM Connection design matches the ACI figure.

Perhaps we should change the wording. Would "Shear Bars Parallel to V3" or "Shear Bars Parallel to Minor Axis" and "Shear Bars Parallel to V2" or "Shear Bars Parallel to Major Axis" be clearer?

RE: Anchor Reinforcement in RAM Connection

Jason McCool — Fri, 07 Apr 2017 13:46:50 GMT

Thanks, Karl. One clarification: in your reply, you said "Shear anchor reinforcement in the major direction increases the shear capacity in the major direction (V2 and Axis 2 below). Shear anchor reinforcement in the major direction increases the shear capacity in the major direction (V3 amd axis 3 below)." I'm assuming that 2nd statement was about the minor axis and not supposed to repeat the word major.

But in RAM Connection Standalone, I'm seeing behavior where the anchor reinforcing shear bars in the minor axis direction are what has to be increased to reduce overstresses in the Major Axis design check for "Group of Anchors reinforcement in shear". Wouldn't this be exactly opposite of what ACI is showing for anchor reinforcing for shear (screenshot below)? My HSS column is in a longitudinal orientation, so the braces - and the shear - should be on the major axis. Therefore the bars to develop that force on the other side of the failure cone would also need to be aligned with the major axis. Am I missing something here, or is this incorrect behavior in RCSA similar to what you described in RE and RSS?

Thanks,

Jason

RE: Anchor Reinforcement in RAM Connection

Karl G — Thu, 06 Apr 2017 14:25:07 GMT

[***Original Post was Edited 4/7/206***]

In RAM Connection Standalone, shear V2 is the major axis shear and is parallel to local axis 2 and shear V3 is the minor axis shear and is parallel to local axis 3. See screen capture below. Shear anchor reinforcement in the major direction increases the shear capacity in the minor direction (V3 and Axis 3 below). Shear anchor reinforcement in the minor direction increases the shear capacity in the major direction (V2 and axis 2 below).

In RAM Elements, the orientation of the column defines the local axis of the column. Like RAM Connection Standalone, Vu2 is the major axis sear and is parallel to the local 2 axis and Vu3 is the minor axis shear and is parallel to the local 3 axis. Like Standalone, I find that anchor reinforcement in the major direction increases the capacity associated with minor direction (Vu3 and local axis 3), and anchor reinforcement in the minor directions increases the capacity associated with the major direction (Vu2 and local axis 2).

In RAM Structural System, the orientation of the column is associated with the angle in the XY Plane. Similar to RAM Elements, Vmajor shear is major axis shear and the same as V2 in the screen capture above and Vminor is the minor axis shear and the same as V3. Like RAM Elements and Standalone, I find that anchor reinforcement in the major direction increases the capacity associated with minor direction (Vu3 and local axis 3), and anchor reinforcement in the minor directions increases the capacity associated with the major direction (Vu2 and local axis 2).