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FixPoint Command

Nodal boundary conditions in FEA analyses can be applied to a single node by using a FixPoint command. The two variations of the FixPoint command select one node. The first one selects a node by coordinates while the second one selects a node from a previously defined key point:

FixPoint (x),(y)
  (Displacement and Load)
  (optional Rotate and/or Select command)
EndFixLine

or

FixPoint (id)
  (Displacement and Load)
  (optional Rotate and/or Select command)
EndFixPoint

where

Within FixPoint blocks, there can be Displacement commands and Load commands to set displacement or load in the x and/or y direction, a Rotate command to rotate the node for skewed boundary conditions, or a Select command to select the node for conditional output of results. The selected node will be assigned each specified boundary condition, rotated or selected.

Notes

  1. When doing axisymmetric FEA, nodes at r=0 will automatically be set to zero velocity in the r directions. You therefore need not set those conditions.
  2. The FixPoint command is only allowed for FEA analyses.