Problem:

The displacement results for all WIND load as were found to be zero, even for extremely high force wind events. Why?

Solution:

There are 3 possible issue that would cause this to occur:

1. No wind has been applied to any segments in the model.

On the Segment tab of the input grids, Apply Wind has not been enabled for any segments, Example Segment A is exposed to wind, but segment B is not.

2. All piping is below ground

The Ground elevation value on the wind dialog screen was set such that all piping is actually below the ground surface where wind load does not affect the piping.

See Load> Wind...> example: the vertical ground elevation is +30 feet

In the example above, the highest vertical node point elevation in the model is 10.67 ft. However, the Wind dialog ground level is set for +30 ft. Therefore the program assumes that all node points below vertical elevation of +30 ft is considered to be below ground. This scenario will result in 0.00" displacement for the wind load case as all piping is considered below ground regardless of the "Apply Wind" segment selection. 

3. Performing a Linear analysis.

There will be no pipe displacements at supports with large gaps if performing a Linear analysis which ignores all Gaps, Friction, and Soil settings. For a given Analysis Set enable Non Linear or Gaps/Friction/Soil check box to consider these settings.

See Also

"Displacement" sub report

Bentley AutoPIPE