How can I model boundary elements for concrete shear walls in ETABS?

Some people say that there are two main ways to model boundary elements in a shear wall using ETABS:

  • Boundary elements could be modeled as columns. In other words, in this way, at first two columns should be created, then a wall should be created between them. With this method, is the stiffness analysis and period calculation right? Because there we have columns and walls at the same node?
  • Draw the wall and its boundary elements in section designer when defining the shear wall. With this method, if we create the extended boundary element, is the extended area calculated in analysis? Because I've tried to create an extended boundary element using section designer and the cumulative mass of the structure has not changed.
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