Step 6: Specify boundary conditions
Set Options
Select in Main Menu:
Solution > Analysis Type > New Analysis > Modal
...
Click OK and then OK again to accept defaults for the Block Lanczos Method.
Apply Displacement Constraints
Select in Preprocessor:
Loads > Define Loads > Apply > Structural > Displacement > On Keypoints
...
Select keypoint at C. Select UY, Enter 0
for Displacement value.
Click OK.
Specify Damping Ratio
Select in Preprocessor:
Loads > Load Step Opts > Time/Frequency > Damping
Enter 0.02 for
Constant damping ratio.
Click OK.
Save your work
Click on SAVE_DB in the ANSYS Toolbar to save the database.
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