| Applies To | |
| Product(s): | AutoPIPE |
| Version(s): | ALL; |
| Environment: | N/A |
| Area: | Load Case |
| Original Author: | Bentley Technical Support Group |
| Date Logged & Current Version | Sept. 2016 10.01.00.09 |
Problem:
Give 2 models with 6 different results. 3 supports have one response spectrum and other 3 supports have a 2nd different response spectrum applied.
Model #1: 1st 3 supports are assigned to Support Group #1 with Response Spectrum A, 2nd set of 3 supports are assigned to Support Group #2 with Response Spectrum B.
Model #2: 1st 3 supports are individually assigned to Support Group #1, #2, #3 respectively with Response Spectrum A, 2nd set of 3 supports are again individually assigned to Support Group #4, #5, #6 respectively with Response Spectrum B.
Should dynamic results for both analysis match exactly, Yes or No?
Why?
Solution:
No, the dynamic results from both models should not match.
Why, see AutoPIPE help "Seismic Anchor Movement Analysis":
The following procedure is used to obtain the SAM results:
1. The global X seismic movements are applied only to the supports and anchors which are specified with the first phase. The supports and anchors associated with the other groups remain fixed. The response of the piping system (forces and moments, support reactions, etc.) is computed for this condition. .....
......
5. The final response is calculated by combining responses of the global X, Y and Z directions using the SRSS combination method.
See help for complete details on this feature.
Again, it's not the response input that's the question, it's the method of application, which is different for the two scenarios. For this reason, the results maybe close but will not exactly match.
See Also
"Sam" (Seismic Anchor Analysis)