Hello,
There is probably a simple and obvious answer to this question but I will ask anyway. Why is it that RAM Connection only deals with the major axis bending moment and vertical shear (and axial) instead of all 3 forces and all 3 moments?
Thanks,
John
It depends on the connection. Most of our connections are based on code specific examples and design guides, so most of them are limited to the forces common for such a connection. Others (like the base plates, moment end plates) will handle forces in more dof.
Hi seth,
I have a similar question. When I found that ram connection, let's say in a moment connection, does not consider all 3 forces and 3 moments, then I thought maybe I would just have to model my structure thinking in advance what forces my connection can only resist.
Like for example, in the apex beam splice.
This kind of connection does not need inputs in minor axis bending and shear along the major axis so to take that into consideration, I made the respective member releases in my model. Upon releasing the shear along the major axis, (since I have lateral loads due to earthquake, there is a node at that point in apex and that apex node has its share of lateral load distribution) that caused instability to my structure. By the way, I released the shear along the major axis for both of the members connected on that apex.
I understand that allowed forces for these connections were only based on code specific examples and design guides as you mentioned but can I ask for an advice for scenarios like these wherein we try to model those limitations in connection forces but get instabilities instead? Should member release only be done on one member and not both? Should we get partial release only instead of full? or should we just completely ignore those forces not considered by connection design (which I think is not the right way)?
Thank you! Your response is appreciated.
I would not typically release members in shear unless there is a real sliding type connection. If you are getting a lot of shear in the minor direction and that's a real circumstance, then you might need to design a custom connection, or add bracing, deck attachment etc.
You are right seth. Releasing members in shear would mean having a sliding type connection. I get your point With that, I think I have to design a custom connection. Thank you!