How to apply Static Seismic G factor to part of the model, instead of the whole model?
When using Load> Static Earthquake, the "G" force are applied to the entire model. To turn off the seismic G force for part of model use AutoPIPE's Insert> Xtra Data> Member & Point Static Earthquake factor commands.
Select part of model you don’t want to apply seismic “G” force. Then click on Insert> Xtra Data> Points Static Earthquake factor and enter ‘zero’ Static earthquake scale factor in all directions. Repeat this step but select Insert> Xtra Data> Member Static Earthquake factor and enter ‘zero’ Static earthquake scale factor in all directions.
During animation of the any seismic load case, one may see the flanges and flanged valves fluctuate but this is just a graphic issue. Upon further review of the results, locations where Point & Member earthquake factors were applied, movement will only be influenced by connected piping that does have a positive seismic load applied. While all isolated piping systems will have no movement under seismic load cases.
The Static G load can be varied at different locations by factoring. To factor all the weight you must use both the member and the point Earthquake factors.
- Member Earthquake Factor (Insert > Xtra Data > Member Earthquake Factor) are applied to weights of pipe, pipe contents, pipe insulation etc...
- Point Earthquake Factor (Insert > Xtra Data > Point Earthquake Factor) are applied to point loads: valve, flange, and added weight.