The Criteria - Ground Level command is used to specify the level at which the ground intersects the structure.

• Select Criteria > Ground Level.
  

  The default is for the ground level to be at the base of the model. In this tutorial the default will be accepted and no changes need be made. When a level other than the base is selected as the ground level two things will happen. First, the program generated loads will be adjusted for the new building height and the forces will be applied to the above ground levels only. Second, the ground level and any level below grade will be laterally restrained as if by a vertical roller.

• Click [OK].