Story: Etabs Mass Summary By

Always verify if you are looking at Mass (e.g., ) or Weight ( ). ETABS reports Mass in this specific table.

Weight). An error in the mass summary directly leads to an incorrect seismic force. Modal Analysis: etabs mass summary by story

The total mass of the building is the fundamental variable in the formula (Base Shear = Seismic Coefficient Always verify if you are looking at Mass (e

Often, the culprit is a massive story mass that ETABS cannot move due to stiff supports. Go back to the Mass Summary, verify the U3 values, and ensure your vertical elements (columns/walls) are not artificially restraining movement. verify the U3 values