The translational mass active in the global X and Y directions. If you converted loads to mass uniformly, these values are typically identical.
If you are facing a (like mismatched mass or twisting modes) in your current ETABS model? What version of ETABS you are using? Share public link
The total translational mass assigned to that story in the X and Y directions. This is calculated as (acceleration due to gravity).
The ETABS Mass Summary by Story table contains several columns. Understanding what each column represents is vital for accurate model verification. Column Name Description etabs mass summary by story
Generating the mass summary by story in ETABS is a straightforward process:
A practical note: when comparing, remember to convert mass to weight ( W = m × g ) if necessary. One engineer reported a 20% discrepancy until discovering they had not included superimposed dead loads (SDL) in the mass source definition. The official CSI answer is: Building mass always refers to the definitions specified in the Define > Mass Sources menu. To account for SDL, add an SDL case to the Load List .
You must have a completed analysis run (the lock icon should be closed). Navigate the Menu: Go to Display > Show Tables . Find the Specific Table: Expand Analysis Results . Expand Structure Results . The translational mass active in the global X
ETABS usually focuses on horizontal inertia for seismic runs.
This is the critical part. ETABS calculates mass in three translational directions:
The mass source is defined in . The three options are: What version of ETABS you are using
In the realm of structural engineering software, CSI ETABS (Extended Three-dimensional Analysis of Building Systems) stands as a cornerstone for the analysis and design of building systems. Among the myriad of output tables and log files it generates, one of the most critical—yet often overlooked—is the .
Are you getting in your table, or are the numbers just not matching your manual estimates ? What elements are included in your Mass Source definition ?
Which (e.g., ASCE 7-22, Eurocode 8) you are designing under?
Your base (foundation level) often has a mass value if you have a basement slab or ground floor. In elevated structures (e.g., podium slabs), ensure mass is not double-counted between the base and first floor.