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TR.22.2 Element Release Specification

This set of commands may be used to release specified degrees of freedoms at the corners of plate finite elements.

General Format

element-list  { J1J2 | J3 | J4 } *{ FXFY | FZ | MX | MY | MZ }


  • J1, J2, J3 and J4 = signify joints in the order of the specification of the element incidence.  For example, if the incidences of the element were defined as 35 42 76 63, J1 represents 35, J2 represents 42, J3 represents 76, and J4 represents 63. 
  • FX through MZ = represents forces/moments to be released per local axis system.
Note: Element releases at multiple joints cannot be specified in a single line. Those must be specified separately as shown below.


Example of Correct Usage

10 TO 50 J1 MX MY
10 TO 50 J2 MX MY
10 TO 50 J3 MY
10 TO 50 J4 MY

Example of Incorrect Usage

10 TO 50 J1 J2 MX MY
10 TO 50 J3 J4 MY


  1. All releases are in the local axis system. See Figure 1.13 for the various degrees of freedom. Fx and Fy have the same sense as Sx and Sy in Figure 1.13. Fz has the same sense as SQx or SQy. Generally, do not over release. The element must still behave as a plate after the releases.

  2. Selfweight is applied at each of the nodes as if there were no releases.

  3. Thermal stresses will include the fixed-end thermal pre-stress as if there were no release.

  4. May not be used with the Element Plane Stress or Element Ignore Inplane Rotation commands on the same element.

  5. Note that the usual definitions of local Mx and My are reversed here. See Figure 1.13 for the definitions of Mx and My. Releasing Fz, Mx, My will release all bending capability. Releasing Fx, Fy, Mz will release all in-plane stiffness.