How to use the SET FLOOR ANGLE TOLERANCE command to help achieve correct floor load generation.
If the program is unable to generate a floor load properly, using the SET FLOOR LOAD TOLERANCE command can often resolve the problem, as described in the following wiki:
How To Use the SET FLOOR LOAD TOLERANCE Command to Ensure Proper Floor Load Generation - RAM | STAAD | ADINA Wiki - RAM | STAAD | ADINA - Bentley Communities
However, if you have added the SET FLOOR LOAD TOLERANCE command to your model and still find that the loading won't work, you can also try the SET FLOOR ANGLE TOLERANCE command. This command is used to specify the tolerance for out-of-plane nodes in terms of an angle (with respect to adjacent nodes in the floor being loaded). The default value is 0.01 degrees, but increasing this number will often allow the floor load generation to work properly in scenarios when previously it did not (especially when you are working with inclined floors.) The SET FLOOR ANGLE TOLERANCE command can be entered in the STAAD Editor as shown below:
It can also be specified in the GUI by going to Analysis and Design -> Miscellaneous Commands -> Set Floor Angle Tolerance: