Perform a Cracked Deflection Analysis

Follow the below instructions to calculate the deflection of a floor system with allowance for loss of bending stiffness due to cracking of either slab regions or beams.

To Perform a Cracked Deflection Analysis:

1. Add a new Load Combination. Make sure to select Cracked Deflection for the combination's Analysis/Design option. An example is highlighted below.

   

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2. Go to the Analysis>Analysis and click the Execute Analysis icon.

3. In the Analysis Option dialog, set the settings you wish to use and make sure to choose all load combinations being used for design including the Cracked Deflection combination(s) in the selection of combinations for analysis.

   Note: It is important to select the strength and service (including initial) combinations that are used to calculate strength reinforcement and code based minimum reinforcement so the program can include the rebar that is required in the section in the Cracked Deflection Analysis.

   

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4. Save the solution when prompted.

   

5. Add support lines to the model.

   

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6. Generate the design sections along the support lines.

   

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7. Enter base reinforcement into the model that you want accounted for in the analysis if any is needed. (Any additional calculated reinforcement needed in the section based on strength or minimum code requirements will be included as well.)

8. Go to Floor Design>Section Design and click the Design the Sections icon.

9. When prompted click YES to save the design solution.

   

10. Go to Floor Design>Rebar and click on the Calculated Rebar Plan icon.

11. View the calculated reinforcement and modify as needed.

12. Go to Analysis> Analysis and click the Cracked Deflection icon.

13. When the analysis finished click OK to save the results.

    

14. Once the results are saved you can View the Cracked Deflection Analysis Results.