Search found 21 matches

by dcizmar
Sun Mar 13, 2011 4:44 am
Forum: OpenSees.exe Users
Topic: Spring element with decreasing stiffness
Replies: 3
Views: 3243

Re: Spring element with decreasing stiffness

vesna wrote: > You can do this by using Hysteretic material: > http://opensees.berkeley.edu/wiki/index.php/Hysteretic_Material. > > With this material you can define three points for each direction and > construct the material you want. Dear Vesna, thanks for quick replay. I tried numerous tests and...
by dcizmar
Tue Mar 08, 2011 2:21 pm
Forum: OpenSees.exe Users
Topic: Spring element with decreasing stiffness
Replies: 3
Views: 3243

Spring element with decreasing stiffness

I am trying to find a way to model a spring which will behave in the way such that when strain is zero, the force in the spring is maximal.
As the strain is increasing, the force should drop (for example linear). I really don't have an idea how to model this.
by dcizmar
Sat Jan 22, 2011 9:09 am
Forum: Documentation
Topic: the reliability part of Opensees
Replies: 5
Views: 20814

Re: the reliability part of Opensees

Any news about reliability part in OS? :)
by dcizmar
Mon Mar 29, 2010 1:36 am
Forum: OpenSees.exe Users
Topic: Recorder doesnt record force in spring
Replies: 1
Views: 2095

Recorder doesnt record force in spring

Strange problem. I cant get force in spring. However, I get spring deformation and when calculate force it it ok so spring is active... :( CODE: model BasicBuilder -ndm 2 -ndf 3 set P 100 set l 121.9; set h 91.44; set E 20600; set a1 1.33; set a2 1.49; set k 1; set I 1 ; node 1 0.0 0. node 2 $l 0.0 ...
by dcizmar
Fri Mar 26, 2010 6:05 am
Forum: OpenSees.exe Users
Topic: Steel structure with spring between elements
Replies: 1
Views: 2107

Steel structure with spring between elements

I am trying to model spring between the element 6 and element 3 in my model. I added joint 5 and via equalDOF connected it with the joint 3. Then made zerolength element. The spring should carry axial load from element 6. There are several things that bother me. 1. I assigned element zeroLength 7 5 ...
by dcizmar
Wed Mar 24, 2010 11:37 pm
Forum: OpenSees.exe Users
Topic: Simple supported beam with spring in the middle
Replies: 4
Views: 4020

Working perfectly. :) Thanks very much.
by dcizmar
Wed Mar 24, 2010 1:50 pm
Forum: OpenSees.exe Users
Topic: Simple supported beam with spring in the middle
Replies: 4
Views: 4020

thanks for replay, I understand what I have done. :oops: ...but I am trying to model a kind of bearing in the middle of the beam. so when the axial stifness of the sping is very large it will become support which will "carry" vertical reaction. How to model this with the zerolength element?
by dcizmar
Wed Mar 24, 2010 2:30 am
Forum: OpenSees.exe Users
Topic: Simple supported beam with spring in the middle
Replies: 4
Views: 4020

Simple supported beam with spring in the middle

Hi. I am trying to model simple spring in order to verify more complex models. However I cant get a force in the spring. I looked at the file 10x times and can't figure this. :D So please if anyone can help! :) model BasicBuilder -ndm 2 -ndf 3 set L 200 set A 20 set E 21000 set I 167 node 1 0.0 0.0 ...
by dcizmar
Mon Nov 02, 2009 11:51 am
Forum: OpenSees.exe Users
Topic: Failure of an element
Replies: 3
Views: 3648

Thanks for your replay Hugo. But please can you be more precise?
by dcizmar
Mon Nov 02, 2009 8:30 am
Forum: OpenSees.exe Users
Topic: Failure of an element
Replies: 3
Views: 3648

Failure of an element

Suppose I want to model cantilever beam axially loaded. I increase load until the strains (or stresses) reach some point when beam fails. How to model this? I tried with hysteretic material without any success. It only extrapolates the stress-strain relationship given by 3 points. However I didn't t...
by dcizmar
Sat Oct 31, 2009 4:38 am
Forum: OpenSees.exe Users
Topic: Parallel model - truss elements
Replies: 4
Views: 4169

it is theoretical model. I intend to take n truss elements. Increase load until first element fails, then the redistribution of the forces will take place. After that I have n-1 element and increase force again (if possible). This won't be static calculation as I am interested in reliability of this...
by dcizmar
Fri Oct 30, 2009 1:49 pm
Forum: OpenSees.exe Users
Topic: Parallel model - truss elements
Replies: 4
Views: 4169

thanks Silvia. :)
so this settles the geometry problem.

but what material to use?
Hysteretic?
how to model failure of an element?
by dcizmar
Fri Oct 30, 2009 9:34 am
Forum: OpenSees.exe Users
Topic: Parallel model - truss elements
Replies: 4
Views: 4169

Parallel model - truss elements

I would like to know if it is possible to make parallel model of n truss elements. I would apply force (and increase) it until first element fails and force redistribution takes place....

Does anybody has idea how to model this?
by dcizmar
Sun Oct 18, 2009 3:53 am
Forum: OpenSees.exe Users
Topic: Reliability part of OpenSees
Replies: 1
Views: 2190

Reliability part of OpenSees

I am wondering is there a manual or some examples for new command syntax in the reliability part of the opensees? If you take new version and try to run Terje's files you can notice that syntax has changed....
by dcizmar
Tue Oct 13, 2009 11:29 am
Forum: Documentation
Topic: the reliability part of Opensees
Replies: 5
Views: 20814

the reliability part of Opensees

I am wondering is there a manual for new commands in the reliability part of the opensees? If you take new version and try to run Terje's file you can notice that syntax has changed....