Page 1 of 2
Regarding Absorbing boundary result
Posted: Mon Jun 06, 2022 4:14 pm
by begumemte1991
Dear team STKO,
The file which is there on your website for 2D soil model validation under the application of ricker wavelet does not give the same result as shown in the webinar available on YouTube. Can you please confirm why is it happening so?
Results from the monitor defined are attached herewith. Also, in the post-processor, it was found that the wave does not reach the surface.
Re: Regarding Absorbing boundary result
Posted: Tue Jun 07, 2022 7:26 am
by STKO Team
I think it's due to a recent change in OpenSees. Now it seems that the Linear algorithm with -factorOnce does not work with the TRBDF2 integrator.
Can you confirm that you are using this combination?
You can either switch-off the -factorOnce option, or use another integrator Like Newmark 0.5 0.25
Re: Regarding Absorbing boundary result
Posted: Tue Jun 07, 2022 8:04 am
by begumemte1991
Yeah, now it is working perfectly fine. I have used Newmark 0.5 0.25. Thank You.
Re: Regarding Absorbing boundary result
Posted: Mon Jun 13, 2022 1:52 pm
by STKO Team
You're welcome
Re: Regarding Absorbing boundary result
Posted: Fri Aug 12, 2022 8:20 am
by begumemte1991
Hello team STKO,
As it is known to us that STKO's automated LK boundaries automatically identify the bottom and side boundaries. Since the bedrock shear-wave velocity and density are much higher than the soil, and the material for LK boundaries is defined only for soil, I wanted to know how STKO is applying motion at the bottom. Does the motion get multiplied with the soil properties or STKO has the ability to consider some bedrock properties and multiply with those properties? Because so far as I know if soil properties are used in converting the acceleration to equivalent forces, the results will not be correct.
Re: Regarding Absorbing boundary result
Posted: Thu Aug 18, 2022 7:35 am
by begumemte1991
Please reply to my query. Thank you.
Re: Regarding Absorbing boundary result
Posted: Mon Aug 22, 2022 8:04 am
by HC2020
Hi Begum,
Sorry for the wait, we have been closed for holidays for the last two weeks.
We will be answering the queries over the next few days.
Thanks for your patience.
Re: Regarding Absorbing boundary result
Posted: Mon Aug 22, 2022 12:43 pm
by STKO Team
As it is known to us that STKO's automated LK boundaries automatically identify the bottom and side boundaries. Since the bedrock shear-wave velocity and density are much higher than the soil, and the material for LK boundaries is defined only for soil, I wanted to know how STKO is applying motion at the bottom. Does the motion get multiplied with the soil properties or STKO has the ability to consider some bedrock properties and multiply with those properties? Because so far as I know if soil properties are used in converting the acceleration to equivalent forces, the results will not be correct.
If at the bottom interface you have bedrock, just create 2 ASDAbsorbingBoundaryMaterials, one with the soil properties (sides) and one with the bedrock properties (bottom)
Re: Regarding Absorbing boundary result
Posted: Tue Aug 23, 2022 7:45 am
by begumemte1991
Thank you for your reply.
If at the bottom interface you have bedrock, just create 2 ASDAbsorbingBoundaryMaterials, one with the soil properties (sides) and one with the bedrock properties (bottom)
Ok, I will do it.
We are planning to update the source code of the ASDAbsorbingBoundary in OpenSees such that you can assign a real material model, instead of G,v and rho. In this way you will be able to directly assign the same material you assign to the interior soil domain.
From the above discussion, I could learn many things. Also as discussed here, for nonlinear soil material are you planning to develop nonlinear absorbing boundaries? If yes, can you please give the tentative date as to when it is going to release? Also, I would request STKO for another webinar on this (considering the nonlinearity of soil like using PDMY material and nonlinear absorbing boundaries).
Re: Regarding Absorbing boundary result
Posted: Fri Aug 26, 2022 8:21 am
by STKO Team
From the above discussion, I could learn many things. Also as discussed here, for nonlinear soil material are you planning to develop nonlinear absorbing boundaries?
Yes
If yes, can you please give the tentative date as to when it is going to release?
I cannot give you a real date, but I hope during September
Also, I would request STKO for another webinar on this (considering the nonlinearity of soil like using PDMY material and nonlinear absorbing boundaries).
Sure, we will do it