Can we apply dynamic load using Opensees?

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ismailqeshta
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Location: RMIT University, Melbourne, Australia

Can we apply dynamic load using Opensees?

Post by ismailqeshta » Sun Mar 04, 2018 3:22 am

Hi,

As far as I know, Opensees provides only static loads, and no dynamic load exists.

Is that correct? if not, it would be great if anyone can show me the specific command/code to do that.


Thank you very much.

erkanbicici
Posts: 3
Joined: Wed Feb 28, 2018 6:30 pm

Re: Can we apply dynamic load using Opensees?

Post by erkanbicici » Mon Mar 05, 2018 8:38 pm

Hi,
You can apply dynamic loading.
Check the opensees example page.
There are several examples about dynamic loading.

selimgunay
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Location: University of California, Berkeley

Re: Can we apply dynamic load using Opensees?

Post by selimgunay » Mon Mar 05, 2018 8:47 pm

Please see the below link as an example of dynamic loading

http://opensees.berkeley.edu/wiki/index ... typical.29

ismailqeshta
Posts: 115
Joined: Mon Feb 20, 2017 1:19 am
Location: RMIT University, Melbourne, Australia

Re: Can we apply dynamic load using Opensees?

Post by ismailqeshta » Mon Mar 05, 2018 9:13 pm

Thank you for your answers.

Selim: Isn't that applied as a static load in the form of cyclic load?

I am looking for a dynamic load where we can define its time-history.

fmk
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Re: Can we apply dynamic load using Opensees?

Post by fmk » Tue Mar 06, 2018 3:05 pm

the examples on that page if you were to care to look at them do multiple different dynamic analysis for an imposed earthquake/

if you want to apply lateral nodes at the loads create a path time series that describes how the load changes with time .. you apply the loads by associating that time series with a load pattern .. in the load pattern specify the reference loads (the applied loads equals the reference loads times the load factor coming from the time series), i.e. if the loads vary in some constant envelope up the height of the building place all the nodes in the load pattern, if vary independently depending on heigh, create a time series and load pattern for each floor and in that pattern just place the nodes of the floor.

anaj
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Joined: Thu Jun 28, 2018 7:25 am

Re: Can we apply dynamic load using Opensees?

Post by anaj » Thu Jun 28, 2018 8:05 am

fmk wrote:
> if you want to apply lateral nodes at the loads create a path time series
> that describes how the load changes with time .. you apply the loads by
> associating that time series with a load pattern .. in the load pattern
> specify the reference loads (the applied loads equals the reference loads
> times the load factor coming from the time series), i.e. if the loads vary
> in some constant envelope up the height of the building place all the nodes
> in the load pattern, if vary independently depending on heigh, create a
> time series and load pattern for each floor and in that pattern just place
> the nodes of the floor.

Hello, I am also trying to apply a dynamic load F(t) on a node.
The node is on the first floor of the structure, not at the base.
I defined the path <timeSeries Path $tag -dt $dt -filePath $filePath>; however, I do not understand how to create the load pattern.

Thank you :)

fmk
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Re: Can we apply dynamic load using Opensees?

Post by fmk » Thu Jun 28, 2018 9:48 am

create a load pattern with a single load on the node you wish to apply the load to .. the load actually applied during the transient analysis will be the value of the load at the node (the pseudo load) TIMES the load factor obtained from the time series.

anaj
Posts: 2
Joined: Thu Jun 28, 2018 7:25 am

Re: Can we apply dynamic load using Opensees?

Post by anaj » Thu Jun 28, 2018 12:08 pm

Thanks, it works now!

fmk wrote:
> create a load pattern with a single load on the node you wish to apply the
> load to .. the load actually applied during the transient analysis will be
> the value of the load at the node (the pseudo load) TIMES the load factor
> obtained from the time series.

nyangi
Posts: 25
Joined: Fri Jun 15, 2018 2:47 am
Location: Huazhong University of Science & Technology,China

Re: Can we apply dynamic load using Opensees?

Post by nyangi » Tue Oct 02, 2018 2:56 am

Can you share with me how managed to apply dyanamic loading(Even with your example it will be ok)
Thank you

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