BWBN Analyses

[vjayaprakash]

Hi Forum,

There is a BWBN hysteresis example on opensees website. http://opensees.berkeley.edu/wiki/index.php/BWBNExample

However there is an error, when one runs the MATLAB code, as the output files are not generated. Could the moderator /FMK kindly look at it.

[vjayaprakash]

1. The 20 earthquake records seem correct.
2. The IDA procedure (SACdynamicals.tcl and SACeqscale.tcl) seem correct.
3. The file Model.tcl seems correct.
4. The MATLAB file run_ops.m seems correct.

5. Could someone check these 2 files: drift_rw_1.m and SACgravity.tcl. There may be problem. (6 directions are USED but the warning states 3 DOFs are DEFINED.)

Thank you.

[IsmBaha]

You need remove 3rd dim properties, this example is old. So fix line 300 something of the "SACgravity.tcl as:

element twoNodeLink 51 251 25 -mat 7 4 7 -dir 1 2 3;# -orient 0 1 0 -1 0 0;
element twoNodeLink 52 261 26 -mat 7 4 7 -dir 1 2 3;# -orient 0 1 0 -1 0 0;
element twoNodeLink 53 271 27 -mat 7 4 7 -dir 1 2 3;# -orient 0 1 0 -1 0 0;
element twoNodeLink 511 281 28 -mat 7 4 7 -dir 1 2 3;# -orient 0 1 0 -1 0 0;
element twoNodeLink 521 291 29 -mat 7 4 7 -dir 1 2 3;# -orient 0 1 0 -1 0 0;
element twoNodeLink 531 301 30 -mat 7 4 7 -dir 1 2 3;# -orient 0 1 0 -1 0 0;
element twoNodeLink 513 311 31 -mat 7 4 7 -dir 1 2 3;# -orient 0 1 0 -1 0 0;
element twoNodeLink 523 321 32 -mat 7 4 7 -dir 1 2 3;# -orient 0 1 0 -1 0 0;
element twoNodeLink 533 331 33 -mat 7 4 7 -dir 1 2 3;# -orient 0 1 0 -1 0 0;

[vjayaprakash]

Thank you very much, IsmBaha. I will fix the code, accordingly.

[vjayaprakash]

For BWBN parameter estimation,
I am facing a MATLAB error with the BWBN simulink code provided on the Opensees Example page. M file and the .MDL file are here -
http://opensees.berkeley.edu/wiki/index ... Estimation

Could someone please help.

[vjayaprakash]

Hi Forum, My hysteresis loops have strength degradation, stiffness degradation, and pinching. I need to consider all three aspects, in my dynamic analyses. However, In Opensees, Bouc Wen model does not consider pinching while BWBN considers pinching, but does not consider degradation. Any suggestions? Has anyone implemented full BWBN model with all three aspects yet... thankyou

[selimgunay]

Do you need to use only the Bouc-wen material? If you consider other materials, there is Hysteretic material and Pinching4 that has strength degradation, stiffness degradation, and pinching.

http://opensees.berkeley.edu/wiki/index ... c_Material
http://opensees.berkeley.edu/wiki/index ... 4_Material

[vjayaprakash]

Thank Selimgunay for your reply. Could I kindly get your email ID?

I am a little new to opensees. I have to calibrate parameters to fit the response of a "connection", which was experimentally tested. The monotonic and cyclic response of the connection is available (experimental force and displacement values). With Bouc Wen, there is a software tool to best-fit parameters.
(https://www.researchgate.net/publicatio ... algorithms)

I am unsure how to calibrate parameters for a connection (not a structure) with Hysteretic/Pinching4.

[clpgeo]

For BWBN parameter estimation,
I am facing a MATLAB error with the BWBN simulink code provided on the Opensees Example page. M file and the .MDL file are here -
http://opensees.berkeley.edu/wiki/index ... Estimation

Could someone please help.

Hello,

I'm trying to access to the link you reported, where I can find some details but not actually download the Example file (BW_pinch.m) and Simulink S-Function (BWBNpinch.mdl) for the pinching parameters estimation. It says "forbitten access to this server".

Where can I download these functions please?

Thank you

Claudio