Search found 17 matches

by assimi
Tue Nov 03, 2020 5:52 pm
Forum: OpenSeesPy
Topic: printA fatal issue
Replies: 2
Views: 1104

Re: printA fatal issue

Thanks for your reply. I guess in the current state, OpenSees can not return the stiffness matrix before performing analysis. As a suggestion, it would be great to achieve the stiffness matrix before analysis. I am not sure if it is possible.
by assimi
Mon Nov 02, 2020 8:24 pm
Forum: OpenSeesPy
Topic: printA fatal issue
Replies: 2
Views: 1104

printA fatal issue

Hi I would like to report a problem that I am not sure if it is a bug. I would like to obtain the stiffness matrix of a truss in openseespy. I use printA and FullGeneral system after ops.analysis. However, if the truss is unstable, it returns this error and quit the python console. It works properly...
by assimi
Tue Apr 02, 2019 6:16 pm
Forum: Reliability Analysis
Topic: invalid command name "reliability"
Replies: 0
Views: 1145

invalid command name "reliability"

Hi all. I want to learn more about reliability analysis features of OpenSees. So, I started with the youtube video of https://www.youtube.com/watch?v=Nsv5otRuWLw. When I tried to run the examples using my standalone OpenSees with ver 2.5. I failed because I got this error: invalid command name "reli...
by assimi
Tue Sep 18, 2018 2:46 am
Forum: OpenSees.exe Users
Topic: uniaxialMaterial Cable
Replies: 1
Views: 1069

Re: uniaxialMaterial Cable

Hi,

Did you find out what is the problem regarding this error?
by assimi
Tue May 30, 2017 2:00 pm
Forum: OpenSees.exe Users
Topic: modeling a simply supported bridge complex eigenvalue
Replies: 5
Views: 2019

Re: modeling a simply supported bridge complex eigenvalue

It got solved, there is a problem in support nodes and it's ambiguously mentioned in the literature.
by assimi
Mon May 29, 2017 3:18 pm
Forum: OpenSees.exe Users
Topic: modeling a simply supported bridge complex eigenvalue
Replies: 5
Views: 2019

Re: modeling a simply supported bridge complex eigenvalue

Dear selimgunay, All units are consistent and in SI. I modified the code as you suggested and replaced the Iz 2.9666e-6 with 8.3333e-07, but no improvement in the result can be seen. The output of the code is as follows, FullGenEigenSolver::solve() - the eigenvalue 9 is complex with magnitude 1.3884...
by assimi
Sun May 28, 2017 8:03 am
Forum: OpenSees.exe Users
Topic: modeling a simply supported bridge complex eigenvalue
Replies: 5
Views: 2019

modeling a simply supported bridge complex eigenvalue

I tried to model a simply supported bridge, but I can't reproduce the results in the literature. The description of the truss is as follows, "To demonstrate the flexibility of the approach, a simply supported bridge is optimized for its weight minimization with several cases of frequency constraints...
by assimi
Tue Apr 04, 2017 3:48 pm
Forum: OpenSees.exe Users
Topic: Finding the natural frequencies of a truss by using OpenSEES
Replies: 4
Views: 1769

Re: Finding the natural frequencies of a truss by using Open

Dear Frank,
I considered the consistent mass and it worked like a charm. Thanks for your incessant help and suggestions. I'm also grateful for this superb OpenSEES that you and your colleagues provided for scientific use freely.
by assimi
Mon Apr 03, 2017 2:56 am
Forum: OpenSees.exe Users
Topic: Finding the natural frequencies of a truss by using OpenSEES
Replies: 4
Views: 1769

Re: Finding the natural frequencies of a truss by using Open

Dear Frank, First of all, thanks for your fruitful comment. I thought again and again about my problem and I'm now sure about that the mass matrix is not correct. An expert suggested me that my model looks ok but I have not yet added the lumped mass. He added that "this is done by declaring a mass e...
by assimi
Wed Mar 29, 2017 7:40 am
Forum: OpenSees.exe Users
Topic: Finding the natural frequencies of a truss by using OpenSEES
Replies: 4
Views: 1769

Finding the natural frequencies of a truss by using OpenSEES

I want to obtain the natural frequencies of a benchmark truss which is famously known as 10-bar planar truss. It consists of 10 truss members and 6 nodes. Two nodes are its supports and other four nodes are free nodes. The modulus elasticity is 6.89e10 and the added non-structural mass to the free n...
by assimi
Fri Dec 30, 2016 4:07 am
Forum: OpenSees.exe Users
Topic: OpenSees on Linux "OpenSuse"
Replies: 2
Views: 1136

Re: OpenSees on Linux "OpenSuse"

As to my knowledge and not practically, I know that first of all you should download the latest stable source code from the repository and compile it with the corresponding MAKEFILE for the version of linux. TCL libraries are essential too. To download the source code from repository you should foll...
by assimi
Wed Dec 28, 2016 3:57 am
Forum: OpenSees.exe Users
Topic: modeling a 25 bar space truss with different loadings
Replies: 0
Views: 897

modeling a 25 bar space truss with different loadings

Hi, I want to model this 25 bar truss benchmark. the schematic of the benchmark and the loading conditions are attached. How can I define this kind of loading in my code? Because there are multiple loading on nodes 1 and 2. Is it possible with multiple pattern plains? In a one sentence, How can I mo...
by assimi
Fri Jul 08, 2016 7:35 am
Forum: OpenSees.exe Users
Topic: my link with MATLAB runs smoothly on mac but not on windows
Replies: 4
Views: 1484

Re: my link with MATLAB runs smoothly on mac but not on wind

First of all, thx for your reply. I'm repeatedly calling it in two sections; first I take stiffness matrix in a file with printA and I check the eigenvalues for stability and second, I run force/displacement analysis and it results in two files which include axial forces and displacement, so I guess...
by assimi
Thu Jul 07, 2016 11:05 pm
Forum: OpenSees.exe Users
Topic: my link with MATLAB runs smoothly on mac but not on windows
Replies: 4
Views: 1484

Re: my link with MATLAB runs smoothly on mac but not on wind

correction : The code runs smoothly on Mac OS X but it crashes without any errors in Windows after hundreds of computations.
by assimi
Thu Jul 07, 2016 11:01 pm
Forum: OpenSees.exe Users
Topic: my link with MATLAB runs smoothly on mac but not on windows
Replies: 4
Views: 1484

my link with MATLAB runs smoothly on mac but not on windows

Hi, I have written a code to find optimal truss structure using evolutionary algorithms. Furthermore, these kind of algorithms are based on numerous computations. my code produces some text outputs and i read them from Matlab, these outputs are stiffness matrix,axial forces and displacements in node...