equalDOF issue

[kavian]

Hi,

I modeled a OCBF with many nodes at each beam-column intersection in order to pin the beams (release their end rotations since they are force-based BCE). I wanted to constraint all these nodes horizontally to a floor master, while also constrain them vertically at each beam-column intersection master node.

I though that was possible since I am constraining differents DOF's of the sames nodes, but I get errors when checking dynamics. The first modes get a NaN period value.

This is my code, any ideas?

Code: Select all

     for iStory in range(2,NStory+1):
         for pier in range(1,NBay+2):
             master_hor = iStory*100+1      # first pier intersection node set as the floor master.
             master_ver = iStory*100+pier  # each beam-column intersection node set as the vertical master at each joint. 
             if pier < NBay+1:
                 auxnode = master_ver+20                  # Beam-column auxiliary nodeTAG to the left (beam end node).
                 ops.equalDOF(master_hor, auxnode, 1)  # constraint this auxnode horizontally to the floor master.
                 ops.equalDOF(master_ver, auxnode, 2)  # constraint this auxnode vertically to the joint vertical master.
            if pier > 1:
                auxnode = master_ver + 40                # Beam-column auxiliary nodeTAG to the right (opposite beam start node).
                 ops.equalDOF(master_hor, auxnode, 1)  # constraint this auxnode horizontally to the floor master.
                 ops.equalDOF(master_ver, auxnode, 2)  # constraint this auxnode vertically to the join vertical master.
                 ops.equalDOF(master_hor, master_ver, 1)  # finally constraint each vertical joint master horizontally to the floor master.

Thank you for any advice!