I want to set the NGA motions' pga, what should i do?

neallee · Post by **neallee** » Tue Apr 14, 2009 6:55 am

In the definition of the commands relative to nga, there is a coefficient named cFactor which can be used to scale the motions .
However, before i search and download the strong ground motion files, i dont know the pga of the records.
For example, i want to calculate the response with the seismic records just with the distLo and distHi parameters set.
i think there should be a target pga parameter there to scale the ground motion automatically.
If there is any other command, which can do such work and i don't know before, please let me know.
Thank you!

Thanks very much!

Best regards,

Ning

Post by **fmk** » Wed Apr 15, 2009 10:31 am

you scale the records by G, not the PGA. i.e. the values in the files are not given with respect to the PGA, but are in units of G.

neallee · Post by **neallee** » Wed Apr 15, 2009 11:54 pm

thanks for your reply.

yes, for the peerdatabase series, there is a parameter $G in the command. Actually, this command is not work well after the peer/smcat website return to work yesterday.
this is the error report
PeerMotion::PeerMotion() - could not find nPts in record, send email opensees-support@berkeley.edu

the motion list file is like this
....
CHICHI/CHY080-N
CHICHI/CHY080-W
CHICHI/NSY-E
CHICHI/NSY-N
CHICHI/TCU084-N
CHICHI/TCU084-W
...

However, the NGA motion series command works very well.

By the way, this test is carried out on Ranger of TACC, could you please check it?

i can't participate the discussion on 22 May. What a pity that i can't go there and discuss with you all...

best wishes,

Ning.

gourik · Post by **gourik** » Thu Aug 20, 2015 1:39 am

Dear admin,

I am also getting the same error while executing one of the prog from TeraGridExamples

PeerMotion::PeerMotion() - could not find nPts in record, send email opensees-support@berkeley.edu
Domain::addLoadPattern - cannot add as LoadPattern with tag2already exists in model
WARNING could not add load pattern to the domain UniformExcitation 2 - Not Printing the GroundMotion
0
while executing
"pattern UniformExcitation 2 1 -accel $Gaccel"
("foreach" body line 23)
invoked from within
"foreach gMotion [glob -nocomplain -directory GM *.AT2] {
if {[expr $count % $numP] == $pid} {

puts "$pid $count $gMotion"
set ok..."
(file "Example2_test1.tcl" line 17)

Please help me regarding this

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I want to set the NGA motions' pga, what should i do?

I want to set the NGA motions' pga, what should i do?

Re: I want to set the NGA motions' pga, what should i do?