Search found 40 matches

by rmandok
Wed Sep 04, 2013 1:51 pm
Forum: OpenSees.exe Users
Topic: Best element to model viscous damper
Replies: 7
Views: 4785

Re: Best element to model viscous damper

Dear Vesna, I can't imagine how silly I am right now but can you please make me an example rather than 45 degrees?
by rmandok
Wed Sep 04, 2013 1:18 pm
Forum: OpenSees.exe Users
Topic: Best element to model viscous damper
Replies: 7
Views: 4785

Re: Best element to model viscous damper

Dear Vesna, How should the orientation define in my case? can I have an example?
by rmandok
Tue Sep 03, 2013 2:19 am
Forum: OpenSees.exe Users
Topic: Differences Between two uniaxialMaterials
Replies: 1
Views: 655

Differences Between two uniaxialMaterials

Hi dear Vesna and dear all. Is ViscousDamper uniaxialMaterial different from defining Viscous uniaxialMaterial and stiffness material in series (Maxwell model)? If there is difference, what are they? (I believe there is, because the results are not the same) Which is preferred to use? Consider this ...
by rmandok
Sat Aug 31, 2013 2:21 pm
Forum: OpenSees.exe Users
Topic: Convergence problem
Replies: 2
Views: 971

Convergence problem

I want to model some kind of semi-active control using viscous damper. for this purpose I used this piece of code: [code] constraints Plain numberer RCM system SparseGeneral -piv test NormDispIncr 1.0e-8 10 algorithm ModifiedNewton integrator Newmark 0.5 0.25 analysis Transient for {set i 1} {$i<[ex...
by rmandok
Sat Aug 31, 2013 9:39 am
Forum: OpenSees.exe Users
Topic: Best element to model viscous damper
Replies: 7
Views: 4785

Best element to model viscous damper

I want to model a brace like viscous damper and As i read other posts it is said that best materials to model this kind is to use truss or zerolength element. I have couple of question about this: 1-I want to model viscous damper with K=1.9e6 (N/m) and Cd=4.0e5 (N.s/m) and alpha=0.6 . I used both tr...
by rmandok
Thu Aug 29, 2013 9:15 pm
Forum: OpenSees.exe Users
Topic: Why do I get this error with ViscousDamper material
Replies: 3
Views: 4245

Re: Why do I get this error with ViscousDamper material

Dear Vesna, As I mentioned above I download the latest version and try again and still i get this error ViscousDamper Model by S. Akcelyan and D.G. Lignos, McGill University WARNING - ForceBeamColumn2d::update - failed to get compatible element forces & deformations for element: 5(dW: << 1.#QNAN) WA...
by rmandok
Wed Aug 28, 2013 11:20 pm
Forum: OpenSees.exe Users
Topic: Why do I get this error with ViscousDamper material
Replies: 3
Views: 4245

Why do I get this error with ViscousDamper material

I want to model viscous damper and according to OpenSees wiki i use this material uniaxialMaterial ViscousDamper $matTag $K $Cd $alpha but when I attempted to run my code, I got this warning: WARNING could not create uniaxialMaterial ViscousDamper while executing "uniaxialMaterial ViscousDamper $Vis...
by rmandok
Sun Aug 18, 2013 5:15 am
Forum: Framework
Topic: What are the exact difference between following elements?
Replies: 1
Views: 781

What are the exact difference between following elements?

I am wondering what are the differences between nonlinearBeamColumn, forceBeamColumn and dispBeamColumn elements and their usages?
Thanks
by rmandok
Sat Aug 17, 2013 11:55 pm
Forum: OpenSees.exe Users
Topic: Calibration of Maxwell Material's Issue
Replies: 2
Views: 722

Calibration of Maxwell Material's Issue

Recently I asked how to model Viscous Damping and I had been directed to this example: [url]http://opensees.berkeley.edu/wiki/index.php/Calibration_of_Maxwell_Material/[/url] I read the explanation of this example and in this example it is discussed that element "forceBeamColumn" should be used for ...
by rmandok
Sat Aug 10, 2013 9:49 pm
Forum: OpenSees.exe Users
Topic: How to model viscous damping
Replies: 1
Views: 593

How to model viscous damping

I want to use viscous dampers in my model but i do not know how to model them (what material and how to model damping).
I will be glad if you help me.
by rmandok
Tue Jul 30, 2013 12:55 am
Forum: Useful Scripts.
Topic: Active and Semi-Active Control in OpenSees
Replies: 0
Views: 1536

Active and Semi-Active Control in OpenSees

Is there any example for usage of active and semi-active dampers in structures? If not, here is my problem. I have moment resisting frame structure and I have a damper and an earthquake record with 40 second duration. I want this damper to damp seismic energy and force from duration 5 to 15 s, and o...
by rmandok
Fri Jul 26, 2013 12:14 am
Forum: OpenSees.exe Users
Topic: Active and Semi-Active Control in OpenSees
Replies: 0
Views: 502

Active and Semi-Active Control in OpenSees

Is there any example for usage of active and semi-active dampers in structures? If not, here is my problem. I have moment resisting frame structure and I have a damper and an earthquake record with 40 second duration. I want this damper to damp seismic energy and force from duration 5 to 15 s, and o...
by rmandok
Tue May 14, 2013 9:47 pm
Forum: OpenSees.exe Users
Topic: Best Material to Have Descending Branch in Pushover Curve
Replies: 2
Views: 1924

Re: Best Material to Have Descending Branch in Pushover Curv

Dear Frank, my frame designed only for gravitational load and is weak and i pushed it to 1 meter. Can you help me with this please? Here is the capacity curve: http://cdn.imghack.se/images/9ad4ac07b81edeb5ec8fd28992114483.jpg (And the first code, above is the OpenSees code for it.) when I change the...
by rmandok
Tue May 14, 2013 11:03 am
Forum: OpenSees.exe Users
Topic: Best Material to Have Descending Branch in Pushover Curve
Replies: 2
Views: 1924

Best Material to Have Descending Branch in Pushover Curve

Hi, I want to do pushover analysis for a simple one storey and one bay frame. I define material with steel01 material and when the analysis done, I couldn't find any descending branch in pushover capacity curve and it is ascending. Is it because the definition of material? Will the problem be solved...
by rmandok
Tue Mar 05, 2013 12:44 pm
Forum: OpenSees.exe Users
Topic: Geometrical Transformation
Replies: 9
Views: 2107

Re: Geometrical Transformation

Dear Arshian
Can you please explain more about corotational geomtransf? so if it is better to use p-delta what is the purpose of using corotational?!