I'm just wondering why ETABS generated 12 mode shapes (why not 10, 8, 6 modes etc). Also, is there any possibility that by visually looking at these mode shapes, you can perhaps "sense" that your building is behaving good or bad?
Is mode shapes depends on the static and load combination that you create?
How will I know what particular load case this particular mode shape came from?
CAn somebody shed light on this matter?