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Overturning Moment Check

 Overturning Moment Check 


Download the Excel File and replace your own story data.

Then go to the Overturning tab and replace story seismic force (Vx) data.



Go to the table- analysis- result- structure result-story forces-change load case to EX+1

Copy Vx data.







Replace Total Dead Load data.


Goto reactions- base reactions- change load to TDL - copy Fz 



Distance (Center of Mass along X/Y):


Go to load pattern, WX/WY– Modify lateral Load–Modify/show– use X ordinate value

Similarly, Y ordinate value.



🏗️ Overturning Moment Check in Structural Engineering Using Excel

In structural engineering, overturning moment refers to the rotational effect caused by lateral forces (such as wind or seismic loads) acting on a structure. Ensuring that a structure can resist these moments is crucial for its stability and safety. This article provides a step-by-step guide on performing an overturning moment check using ETABS and Excel.

📘 Understanding Overturning Moment

Overturning moments are generated when lateral forces cause a structure to rotate about its base. To prevent failure, the resisting moment (primarily from the structure's weight) must counteract the overturning moment. The Factor of Safety (FoS) against overturning is calculated as:(Civils.ai, SkyCiv Structural Analysis Software)

(Eng-Tips)

A FoS greater than or equal to 2.0 is typically recommended for structural stability. (SkyCiv Structural Analysis Software)

🧪 Performing Overturning Moment Check Using ETABS and Excel

To assess the overturning moment:

  1. Model the Structure in ETABS:

    • Ensure all structural elements and load cases (e.g., seismic loads EX+1) are accurately defined.

  2. Run the Analysis:

    • Perform the analysis to obtain base reactions and story forces.(YouTube)

  3. Extract Seismic Force Data:

    • Navigate to Display → Show Tables → Analysis Results → Structure Results → Story Forces.

    • Change the load case to EX+1.

    • Copy the Vx (lateral force) data for each story.

  4. Extract Dead Load Data:

    • Navigate to Display → Show Tables → Analysis Results → Reactions → Base Reactions.

    • Change the load case to Total Dead Load (TDL).

    • Copy the Fz (vertical force) data.

  5. Determine Center of Mass Coordinates:

    • Go to Define → Load Patterns → WX or WY → Modify Lateral Load.

    • Note the X and Y ordinate values, representing the center of mass distances.

  6. Use Excel for Overturning Moment Calculation:

    • Input the extracted data into a pre-formatted Excel template.

    • Calculate the overturning moment by multiplying the lateral force (Vx) by the height of each story.

    • Calculate the resisting moment by multiplying the vertical force (Fz) by the distance from the center of mass.

    • Compute the Factor of Safety and assess whether it meets the recommended criteria.(Eng-Tips)

📥 Download Overturning Moment Check Excel Template

For a practical application, you can download a pre-formatted Excel template to perform overturning moment checks:

👉 Download Excel

📚 Further Reading