***Gravity Load Application Failed!!!

[mklahyghan]

Hi,

I am using a space frame building model which is of the same format as in Dr. Curt Haselton's models on the page

http://www.csuchico.edu/structural/rese ... base.shtml

To create a new model I have downloaded the zip file from the following link

http://www.csuchico.edu/structural/docu ... ks/4-3.zip

A zip file was be downloaded which contains a file named ModelCodePastedFromExcelVBA.tcl

I have defined all the parameters of the new model in the same format of this file and changed the Acol, ABm, Econcr and Building Geometry parameters in the file DefineVariablesAtMeanValues.tcl

I am trying to run "RunMeanAnalysis.tcl" in Opensees.exe but I am encountering the following error

WARNING SuperLU::solve(void)- Error 2 returned in factorization dgstrf()
WARNING NewtonRaphson::solveCurrentStep() -the LinearSysOfEqn failed in solve()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at
load factor 0.2
OpenSees > analyze failed, returned: -3 error flag
*** Gravity Load application failed!!!

I have checked the connectivity of elements a number of times and there doesn't seem to be an error with that. A forum post previously suggested to check the theta_cap for the model to ensure it is not zero. My lowest value is 0.007904026 (is it too low?). I wish to know where else the error might be.

I would be highly grateful if you could help me. Thank You.

[fmk]

if the original ran i suggest you start with the working version and then make incremental changes to that until you find out what change is casuing the problem. if the original fails send curt an email.

[mklahyghan]

Thank You very much Sir.

The original code from Prof. Curt Haselton worked

I later started commenting out the code to convert the 4 story-3 bay structure to 3 story- 2 bay structure and that is when the error arises. I ensured that the nodes are properly defined with respect to a 3 story- 2 bay structure and also modelled the Joint 2D elements accordingly.

[mklahyghan]

The problem was solved.

The leaning column needed some non-zero stiffness for the structure to be stable. Previously as I was giving a zero stiffness it was unable to apply the gravity loads.

[Prafullamalla]

Is it possible to obtain the code

[selimgunay]

You can find an example with leaning columns here: https://opensees.berkeley.edu/wiki/inde ... ment_Frame

[Niclas]

You need some non-zero stiffness for the structure to be stable.
https://www.sourcingallies.com/
https://www.ulne.se/