Modification of SACS input file and running SACS analysis through command line?

Hello everyone!

I have two queries:

1)  Can I modify the SACS input file through DATAGEN,( changing only the values of diameter and thickness of member groups) then run basic analysis on the modified input file? or will I need to make other changes like the K factor values through the PRECEDE modeler ?

2) Can I make SACS open input files and run basic analysis through the command line without the use of its GUI?

In essence, I'm trying to modify models and run analysis without interacting with its GUI, any ideas on how to go about it?

Thanks in advance!

  • 1) All model properties can be modified using DATAGEN.
    2) SACS does not support running analyses through the command line, you must execute the analysis from the SACS Executive.

    Perhaps you could use a scripting/automation tool to do what you want. You could record the steps to run an analysis and then modify the script.
  • I'm curious as to what are you trying to do exactly, whats the reason for running without the GUI?

    This is a test

  • Thank you Bill and Phil for your responses!,

    "Perhaps you could use a scripting/automation tool to do what you want..."

    Question: what specific automation tool is compatible with SACS? will any windows scripting tool work ?

    "I'm curious as to what are you trying to do exactly, whats the reason for running without the GUI?"...

    I am trying to implement an optimization algorithm to minimize the structures weight (as a part of my masters thesis).
    I am planning to do this by optimizing the member details( i.e. reducing the diameter and thickness of the members).
    The optimization is being done externally by MATLAB, which reads the sacsinp. file (sacs input file) and reduces the diameter and thickness and rewrites the the sacsinp. file.

    Then I need to make SACS run basic static analysis on the modified sacsinp. file to check if the modified model is o.k.

    Then the MATLAB optimizing algorithm again reads the analysed output data file( sacslst. file) which contains the member unity check values, which I'm using as my constraints for the members optimization (i.e the members diameter and thickness are reduced till the member unity check value don't exceed 1)

    This process, i.e SACS analysis, then MATLAB optimization , then SACS analysis on modified members need to be done in a 'loop' till the minimum possible member specs are reached within the acceptable unity checks.

    So the reason for not using the GUI is to avoid the hundreds of possible back and forth data exchanges between the programs.

    Any thoughts on this are a welcomed!
  • We don't prefer a particular automation tool. Any automation tool that can record/replay a series of steps performed on the GUI will do. Also, SACS 5.7 has the ability to create a SQLite database containing the analysis results. You could use this database to get the UC values instead of parsing the output listing file.
  • I am doing the similar thing. Have you found how to call SACS through Matlab? I tried the following command:
    dos( ' "C:\Program Files (x86)\Bentley\Engineering\SACS 5.7 V8i SS4\SACSExecutive.exe" -b -i "sac.runx" -o "saclst"').
    It was able to open SACS but could not run the input file.

    Anyone has ever done this? Any suggestion on this will be greatly appreciated.

    Many thanks!