Question
Asked 28th Jun, 2017
How do I include gravity force in an explicit dynamic analysis in Abaqus? (I don't want only the initial stress field).
I am modeling the impact of an object on a pipeline in Abaqus. I want to include the effect of gravity in the explicit analysis in order to counter uplift of pipe. Any ideas?
I don't want to insert just the initial stress field, as the gravity force will not be present during the dynamic analysis.
Thanks
Most recent answer
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All Answers (5)
American Bureau of Shipping
Two ways:
1) use abaqus import analysis feature with gravity loading in static step, followed by explicit analysis where the gravity load is still active
2) run two step explicit procedure with gravity loading in a quasi-static manner depending upon the frequency of system, followed by impact problem
p.s. impact is a high speed event, and not accounting for gravity/dead loading would give you more conservative results
1 Recommendation
Delft University of Technology
Dear Abhimanyu Kumar and Ar Ko, thank you both very much for your answers.
I 've implemented both your approaches plus I've also run the analysis implicitly with a very very small increment in order to compare results.
Indeed, during the impact the accelerations that the structure experiences for a 10m/s impact are 35-50G, which makes gravity for the impact duration negligible.
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