force time history

[javidsharifi]

Dear all,

I'm desperately in need of help. is there a way in opensees i can introduce the earthquake-induced force time history to the system?
I have modeled a soil-structure system and also calculated the time history of forces caused by the input motion. now, as far as i see it is quite easy to introduce the acceleration, velocity or displacement time history as the input motion to the system. but not yet have i could found a way to introduce the force time history as the input to run the analysis. What should i do?
I greatly appreciate kind helps.

B. JavidSharifi

[fmk]

define what you mean by force time history and were you would apply the loads. if simply a time varying nodal load, apply a 1.0 value for the reference load and use the Path time series for the time series. of course, if the loads at the different nodes change by a different amount at each time step you would need a pattern and time series for each load and possibly one for each nodal dof.

the alternative is to simply write source code to do what you want.

in future, only post the same question in one forum!