Etabs Mass Summary By Story →

For seismic weight (W), ASCE 7-22 Section 12.7.2 states: "The seismic weight shall include all dead load plus applicable partition load and 25% of floor live load." Your mass source must reflect this.

Before generating the report, ensure your mass is calculated based on the correct load patterns. : Go to Define > Mass Source . Typical Settings : Select Specified Load Patterns and add: Dead/Super Dead : Multiplier of 1.0 . etabs mass summary by story

Before dissecting the table itself, it is vital to understand why ETABS compiles this data. In structural dynamics, the equation of motion is governed by mass ($M$), stiffness ($K$), and damping ($C$). For seismic weight (W), ASCE 7-22 Section 12

To master the output, you must master the input. ETABS does not magically know the mass. It uses the following hierarchy: Typical Settings : Select Specified Load Patterns and