Internally in the analysis model ETABS creates two joints at locations where panel zones are assigned to joint objects. If the panel zone is between a column and a beam, one of the joints is connected to the column and one is connected to the beam. Column-brace and brace-beam panel zones are similar.
ETABS reports the following panel zone displacements, internal deformations, and internal forces. Do not confuse panel zone displacements and internal deformations. They are different.
Panel Zone Displacements
ETABS reports displacements for a joint object with a panel zone assignment as follows:
Beam-Column Connectivity: Displacements are reported for the joint connected to the column.
Beam-Brace Connectivity: Displacements are reported for the joint connected to the beam.
Brace-Column Connectivity: Displacements are reported for the joint connected to the column.
Panel zone displacements are reported in the global coordinate system. Positive translational displacements are in the same direction as the positive global axes. The sense of positive rotations can be determined using the right-hand rule.
Panel Zone Internal Deformations
Panel zone internal deformations are calculated as described for link element internal forces. They are reported in the panel zone local coordinate system. The following conventions are used by ETABS:
Beam-Column Connectivity: The i-end of the panel zone is the joint that is connected to the columns. The j-end of the panel zone is the joint that is connected to the beams.
Beam-Brace Connectivity: The i-end of the panel zone is the joint that is connected to the beams. The j-end of the panel zone is the joint that is connected to the braces.
Brace-Column Connectivity: The i-end of the panel zone is the joint that is connected to the columns. The j-end of the panel zone is the joint that is connected to the braces.
Panel Zone Internal Forces
The panel zone internal forces give you a sense of how much unbalanced load is transferred through the panel zone. For example, in a panel zone with beam-column connectivity the internal forces tell you how much unbalanced moment is transferred from the beams to the columns.
Panel zone internal forces are calculated as described for link element internal forces. Because panel zone elements are zero length elements, M2 = M2b and M3 = M3b. The panel zone internal forces are reported in the panel zone local coordinate system.