I am designing an equipment foundation and anchors for a piece of equipment. In Risa 3D, I have located the anchors and drawn a vertical rigid link from center of foundation to top of concrete distance, using a fixed end condition at the node which would be at the center of the foundation. There is a total of 6 anchors. From the top of the vertical rigid links representing the anchor bolts, i have drawn rigid links all to the center of gravity of the equipment where i would add a single nodal load for DL, LL, Wind Load, etc.
My question is, will all the rigid links have fixed ends, creating a completely rigid frame? I plan on using the reactions at the anchor nodes. I have tried pin connections for the rigid links to the center of gravity, but get much larger shear reactions at the anchors, so i believe a completely rigid frame would make more sense. I will transfer the model into Risa Foundation to do the concrete design.