peer ground motion

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susan
Posts: 110
Joined: Sun Mar 02, 2008 12:10 am

peer ground motion

Post by susan »

Hi all,

For peer ground motions (like below), does opensees read the values horizontally or vertically?

PACIFIC ENGINEERING AND ANALYSIS STRONG-MOTION DATA
BORREGO MOUNTAIN 04/09/68 0230, EL CENTRO ARRAY #9, 270
ACCELERATION TIME HISTORY IN UNITS OF G
NPTS= 4000, DT= .01000 SEC
-.1368849E-02 -.1659410E-02 -.1466880E-02 -.6865326E-03 -.6491235E-03
-.6172128E-03 -.5942289E-03 -.5720329E-03 -.5517003E-03 -.5367939E-03
-.5300330E-03 -.5315104E-03 -.5389920E-03 -.5492582E-03 -.5592027E-03
fmk
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Re: peer ground motion

Post by fmk »

depends on the script you have .. the scripts that are provided with the examples would cause opensees to read across a line and then down to the next line to get next value.
susan
Posts: 110
Joined: Sun Mar 02, 2008 12:10 am

Re: peer ground motion

Post by susan »

thanks for your response. I use the default commands:

timeSeries Path 1000 -dt 0.01 -filePath elcentro.acc -factor 9.8;
pattern UniformExcitation 2 1 -accel 1001;

so, it reads the accelerations horizontally...
fmk
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Re: peer ground motion

Post by fmk »

yes
yegoroff
Posts: 9
Joined: Thu Jan 22, 2015 12:00 pm
Location: Newcastle University

Re: peer ground motion

Post by yegoroff »

You should read them horizontally and it would be good to provide the script with the file, which has got only one number in a row.

Additionally, quite often you may want to apply the earthquake scaled to a certain peak ground acceleration, which cannot be done using the record handler from the examples.

Here is my handler of PEER records: https://www.dropbox.com/s/en5lwe9hmln5sxf/ParseAT2.tcl

This one creates two files - one is the original unscaled record in the right format and the second one is scaled to the desired PGA.

This script also creates global variables NPTS, DT and PGA so they could be later used in the script.
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