By Story Better — Etabs Mass Summary

Mastering ETABS Mass Summary by Story: Better Analysis & Seismic Design

Mastering Seismic Analysis: Why ETABS Mass Summary by Story is Better for Structural Engineers etabs mass summary by story better

The story-based mass summary provides a high-level overview perfect for peer reviews and senior principal approvals. Mastering ETABS Mass Summary by Story: Better Analysis

The Mass Summary by Story table condenses this massive sea of data into a single, clean row per floor. You can instantly see the total mass ( ) and mass moments of inertia ( ) assigned to each level. 2. Instant Verification of Mass Source and Distribution If you skip this, the program uses only

By default, ETABS does not automatically include all gravity loads. It uses the Mass Source defined in Define > Mass Source . If you skip this, the program uses only the self-mass of elements—which will dramatically undervalue your seismic weight.

A junior engineer noticed the Mass Summary by Story showed only 1,200 kips of mass at the ground floor, while the architectural takeoff showed 1,800 kips.

This is the most reliable number. It should equal the total dead load plus applicable live load on that floor. Check: Does the mass at the roof match the cladding, roofing, and mechanical units? A discrepancy here means your diaphragm constraints or area loads are incorrectly assigned.