Explanation of Member End Release Codes
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    Coding is either 3 digit [RZ,TY,TX]  or "Y" or "N"

    Axial force is always release in stringers unless use numeric release coding.

    * blank is default "Y"   --> [101]
   
    * "Y" Release Moment [hinge] --> [101]
   
    * "N" Don't Release Moment [continuous] --> [001]