Etabs Mass Summary By Story Now
Ensure all slabs are constrained to a diaphragm to get a clean story-by-story readout.
The standard table has a simple, columnar layout listing each story and its corresponding mass. A typical example from a project in Ecuador shows the mass at each story in kilograms (kg) for the horizontal UX and UV (UY) directions:
The "Mass Summary by Story" is far more than just a data table; it's a fundamental check for the structural engineer. Treat it as a critical quality assurance tool. Before running any dynamic analysis, always review this table. A story-by-story check of your model's mass distribution is an essential best practice that can save countless hours of troubleshooting later.
To access the summary:
The is not just a table—it is the DNA of your structural model. Garbage mass leads to garbage periods, garbage base shear, and ultimately, an unsafe design.
ETABS calculates the Center of Mass (CM) automatically.
Compare adjacent floors. If any story mass exceeds 150% of an adjacent story's mass, your building has a Mass Irregularity , which may require dynamic Response Spectrum Analysis instead of simpler Equivalent Lateral Force procedures.
You can access this summary in three ways:
The is far more than a routine output table. It is the structural engineer’s first line of defense against incorrect seismic modeling. By understanding how mass is calculated—from the mass source definition to the lumping onto diaphragms—you can diagnose hidden errors, validate your model’s behavior, and confidently proceed to response spectrum analysis.
A typical Mass Summary by Story table includes the following columns:
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 .
Extracting this data in ETABS takes only a few clicks. Follow these steps:
Many users assume ETABS uses the same load combinations for mass. By default, ETABS uses Dead Load (1.0) and Live Load (0.0). For seismic design, you must define a proper mass source via: Define > Mass Source > Add New Mass Source .
When presenting a "Mass Summary by Story" in a structural report, you should include:
Always double-check your current unit system in the bottom right corner of the ETABS window. Mass is reported in mass units (e.g., Toncap T o n ), not force units (
Ensure all slabs are constrained to a diaphragm to get a clean story-by-story readout.
The standard table has a simple, columnar layout listing each story and its corresponding mass. A typical example from a project in Ecuador shows the mass at each story in kilograms (kg) for the horizontal UX and UV (UY) directions:
The "Mass Summary by Story" is far more than just a data table; it's a fundamental check for the structural engineer. Treat it as a critical quality assurance tool. Before running any dynamic analysis, always review this table. A story-by-story check of your model's mass distribution is an essential best practice that can save countless hours of troubleshooting later.
To access the summary:
The is not just a table—it is the DNA of your structural model. Garbage mass leads to garbage periods, garbage base shear, and ultimately, an unsafe design.
ETABS calculates the Center of Mass (CM) automatically.
Compare adjacent floors. If any story mass exceeds 150% of an adjacent story's mass, your building has a Mass Irregularity , which may require dynamic Response Spectrum Analysis instead of simpler Equivalent Lateral Force procedures.
You can access this summary in three ways:
The is far more than a routine output table. It is the structural engineer’s first line of defense against incorrect seismic modeling. By understanding how mass is calculated—from the mass source definition to the lumping onto diaphragms—you can diagnose hidden errors, validate your model’s behavior, and confidently proceed to response spectrum analysis.
A typical Mass Summary by Story table includes the following columns:
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 .
Extracting this data in ETABS takes only a few clicks. Follow these steps:
Many users assume ETABS uses the same load combinations for mass. By default, ETABS uses Dead Load (1.0) and Live Load (0.0). For seismic design, you must define a proper mass source via: Define > Mass Source > Add New Mass Source .
When presenting a "Mass Summary by Story" in a structural report, you should include:
Always double-check your current unit system in the bottom right corner of the ETABS window. Mass is reported in mass units (e.g., Toncap T o n ), not force units (
