Etabs — Mass Summary By Story Better

: If your model uses diaphragms, also include the Center of Mass and Rigidity table to show eccentricity. 3. Verification & Quality Checks

To create a professional and comprehensive ETABS story mass summary report, you should organize your findings into a clear structure that includes modeling assumptions, primary data tables, and verification checks. etabs mass summary by story better

💡 Always compare the Total Mass in the summary table to the Base Reaction for a dead load case. They should be identical. If they aren't, your mass source is likely missing a specific load pattern. : If your model uses diaphragms, also include

| Symptom | Likely Cause | Fix | | :--- | :--- | :--- | | Mass at roof is too high | Penthouses, water tanks not modeled as separate stories | Assign point mass or model as a dummy story | | Mass is negative or zero | Invalid constraint or bi-axial hinge | Check Display > Show Undeformed > Joints for errors | | Cumulative mass changes after analysis | Mass source relies on load-dependent deflection (e.g., nonlinear) | Use linear static for mass source | | Mass differs between ETABS and Excel takeoff | Line loads, area loads not converted to mass | Convert all Uniform Loads to Mass via Assign > Area Loads > To Mass | 💡 Always compare the Total Mass in the