seismic sequences
seismic sequences
Dear Seismosoft,
I have three earthquake (defined with three different curves in seismostruct) with three different dt. I want to analyze a frame under these earthquakes as a seismic sequences. How can I do that? Is it possible in Seismostruct without any further works on seismograms?
Is the following method true?:
1_ apply all three earthquakes to the base nodes
2_ define the first earthquake with a curve starts from 0 to 40, without delay.
3_ define the second earthquake with a curve starts from 0 to 55, with delay equal to 40 sec.
4_ define the third earthquake with a curve starts fron 0 to 35, with a delay equal to 40+55=95 sec.
Also, in defining each curve, the amounts of dt should be consider based on dt1, dt2, dt3? Three stages? Is it true?
I have three earthquake (defined with three different curves in seismostruct) with three different dt. I want to analyze a frame under these earthquakes as a seismic sequences. How can I do that? Is it possible in Seismostruct without any further works on seismograms?
Is the following method true?:
1_ apply all three earthquakes to the base nodes
2_ define the first earthquake with a curve starts from 0 to 40, without delay.
3_ define the second earthquake with a curve starts from 0 to 55, with delay equal to 40 sec.
4_ define the third earthquake with a curve starts fron 0 to 35, with a delay equal to 40+55=95 sec.
Also, in defining each curve, the amounts of dt should be consider based on dt1, dt2, dt3? Three stages? Is it true?
- seismosoft
- Posts: 1184
- Joined: 06 Jul 2007, 04:55
Re: seismic sequences
In SeismoStruct it is not possible to apply a 'delay' to the records. However, it is possible to define the records with the 'correct' time at the different stages (e.g. your second record could have a time between 40 and 55 sec).
Further, in the same module it is possible to define multiple stages, so that to adapt the time-step dt according to the intended accuracy and the convergence difficulties of the analysis
Seismosoft Support
Further, in the same module it is possible to define multiple stages, so that to adapt the time-step dt according to the intended accuracy and the convergence difficulties of the analysis
Seismosoft Support
Re: seismic sequences
Thank you for the response. As I understood, I have to change the time of the second record so that its starting point should equal to 40 sec. Did I get it right?
Re: seismic sequences
Dear newman,
When you load a new curve, there is the "Delay" option available in the "Input File Parameters" where you can define the time at which a particular time-history starts being applied to the structure.
When you load a new curve, there is the "Delay" option available in the "Input File Parameters" where you can define the time at which a particular time-history starts being applied to the structure.
Zoi Gronti
Seismosoft Srl.
Seismosoft Srl.
Re: seismic sequences
Hi , i have a question
If the earthquake time about 100s ,can we applied peak time(about 20s) ,for running IDA analysis?
(To take maximum inter story drift)
If the earthquake time about 100s ,can we applied peak time(about 20s) ,for running IDA analysis?
(To take maximum inter story drift)
- seismosoft
- Posts: 1184
- Joined: 06 Jul 2007, 04:55
Re: seismic sequences
Not sure what you mean Prestige. If you have a record of 100 sec, you can only run the first 20 sec by defining correctly the time-history stages.
Seismosoft Support
Seismosoft Support
Re: seismic sequences
tanks for answer my question
your idea is true.
your idea is true.
Re: seismic sequences
hi
i have a question
i want to do IDA analysis to obtain maximum response(such as peak drift,..) and the applied earthquake is San Fernando with 79.44 sec time duration, if i use the stage step time until 22 sec (peak of earthquake occur in 7 sec).
the seismic sequences is it true?
i have a question
i want to do IDA analysis to obtain maximum response(such as peak drift,..) and the applied earthquake is San Fernando with 79.44 sec time duration, if i use the stage step time until 22 sec (peak of earthquake occur in 7 sec).
the seismic sequences is it true?
Re: seismic sequences
I don't believe you can rely on the results, prestige. Just because the peak ground acceleration occurs at 7 seconds, doesn't necessarily mean that the maximum structural response has been achieved by 22 seconds. There could be lower amplitude ground motion with frequency content significant to structural response beyond 22 seconds of the record. Could you capture the maximum response by running only 22 seconds? Possibly. But you cannot be certain of it. The safe choice is to run the entire record.
Tim Huff
Re: seismic sequences
tank Tim Huff
Perhaps your point is correct, but the view of other researchers is that the maximum response takes place at the most effective time, which is the maximum acceleration.
in IDA analysis ,If I want to apply the whole time of the earthquake, it can not be more than seven points scale factor because the output volume exceeds 2GB.
In order to apply more scale factor points, the duration of the earthquake should be considered less.
what is your opinion?
Perhaps your point is correct, but the view of other researchers is that the maximum response takes place at the most effective time, which is the maximum acceleration.
in IDA analysis ,If I want to apply the whole time of the earthquake, it can not be more than seven points scale factor because the output volume exceeds 2GB.
In order to apply more scale factor points, the duration of the earthquake should be considered less.
what is your opinion?