how to set parameter for "[sectionForce 1 1 2]"

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how to set parameter for "[sectionForce 1 1 2]"

Post by rafal » Tue Jul 14, 2015 9:49 am

In the pdf report:
Summary of Work on OpenSees Reliability/Optimization/Sensitivity
Michael H. Scott and Kevin R. Mackie
November 5, 2012

There is an example of a portal frame for which there are assigned two performance functions. One for displacement and the other for element force. In the old version of Opensees Sensitivity/Reliability module the nodal and element response where defined directly in performanceFunction:
performanceFunction 76 ‘‘0.15-\[nodeDisp 2 1\]’’
performanceFunction 23 ‘‘1500.0+\[sectionForce 1 1 2\]’’

Later it has been modified so now it is:
parameter 23 node 2 disp 1
performanceFunction 76 "0.15-\$par(23)"

However the parameter definition for the element response is not present in the portalFrame.tcl EXAMPLES directory.

I cannot figure out what is the right syntax for [sectionForce 1 1 2]?
The following does not work:

parameter 33 element 1 section 1 force 2
performanceFunction 23 "1500.0+\$par(33)"

giving this warning in Opensees:

Parameter::addComponent 33 -- no objects were able to identify parameter section 1 force 2

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Re: how to set parameter for "[sectionForce 1 1 2]"

Post by henryluo » Thu Mar 14, 2019 9:12 pm

Hi, I also encounter the same problem when applying the command "addToparameter". The existing random variables can not be assigned to the materials in the fiber section and even the element load. "addComponent x --no objects were able to identify parameter” occurs on the window. I have tried many types of expressions, e.g. :
addToParameter 1 element $i section 1001 fibersection 1 material 1 fc
addToParameter 2 element $i section 1001 fibersection 1 material 2 fy
(1001 is the section tag for section aggregator and concrete 01 and steel 01 materials are used)
addToParameter 3 loadPattern 2 elementLoad $j wy

Have you found some information about this issue? Thanks in advance.

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