problem with multiple displacement load step
problem with multiple displacement load step
(OP)
I'm performing a two load step analysis. In the first step I'm pre-loading the structure at two key points (points 1 and 3) by applying a displacement condition. In the second step, once the structure is preloaded, I'm actuating the structure from a third key point (point 4), again by a displacement condition (no force is applied). The problem is the following, during the first load step, point 4 suffers some displacement from its initial position, now, during the second load step I would expect the point 4 would displace from its actual position (solution given by first load step) to the given displacement condition, but instead, ANSYS snaps the structure to a configuration where point 4 is again in the initial position and then applies the given displacement, while the pre-stress is still in consideration. This ANSYS files attached as well as a figure, where the displacement of point 4 is plotted against the pseudo-time. the upper figure shows the actual result, the lower figure shows, what I would be expecting and I'm not getting.





RE: problem with multiple displacement load step
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RE: problem with multiple displacement load step
Do you have any idea, how can I make then, that the second load step applies the displacement condition, starting from the deformed position after the first load step?
Or this is just not possible?
RE: problem with multiple displacement load step
As I say, I'm not sure of your model details. Maybe you need to consider applying a UX constraint of zero at KP 4 in the first load step, and then applying your actuation at KP 4 in the second?
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RE: problem with multiple displacement load step
Should be zero, don't you think? (because displacement of -2.19 is the displacement for equilibrium at kp4 just with pre-loading at kp 1 and 3)
Thanks again for your help!
RE: problem with multiple displacement load step
The important thing is that your boundary conditions represent those in your physical system.
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