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To indicate that any story is rigid in one direction, it is sufficient to mark the Rigid -X and / or Rigid-Y boxes box of the relevant story. To uncheck a story marked as rigid, you must check the box on the bottom line. If you do not have any rigid stories in your building, it will be enough to click on the boxes in the Elevation from ground row. The elevation from ground line does not represent a story and this line cannot be intervened by the user.
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