Understanding the mass distribution of a building is the foundation of accurate seismic analysis. In ETABS, the "Mass Summary by Story" table is your primary diagnostic tool for verifying that your mathematical model reflects physical reality.
Cumulative mass from the top down; used to check total building weight.
If your Mass Summary by Story looks "wrong" compared to your manual hand calculations, check these three areas: etabs mass summary by story better
Seismic forces are calculated based on mass. If your story mass is off, your base shear and lateral forces will be incorrect. This table allows you to: Verify the self-weight of slabs, beams, and columns.
Ensure you haven't modeled a slab over a slab, which doubles the mass in that specific story. Understanding the mass distribution of a building is
If you'd like to dive deeper into the technical side, I can help you with: The for mass source. How to export this data to Excel for faster reporting.
Mass moments of inertia; critical for capturing torsional effects. If your Mass Summary by Story looks "wrong"
Check if superimposed dead loads (SIDL) are applied correctly.