Search found 26 matches

by hshoar
Mon Sep 23, 2013 8:16 am
Forum: OpenSees.exe Users
Topic: Plastic hinge which considers P-M interaction
Replies: 9
Views: 2937

Plastic hinge which considers P-M interaction

Hello I need to define plastic hinges for a 2D steel structure. I am investigating progressive collapse resistance capacity of x-braced steel dual systems. The only material which seems to be right according to progressive collapse guidelines is Modified Ibarra-Medina-Krawinklerear Bilin Material ma...
by hshoar
Sat Sep 07, 2013 11:35 pm
Forum: OpenSees.exe Users
Topic: Concept of ZeroLength Element
Replies: 3
Views: 720

Re: Concept of ZeroLength Element

Thank you Prof. Scott After reading your reply and observing an example of opensees which models plastic concentrated hinges using zerolength elements, I almost got what is zerolength element, but, I have other questions too. First one is how can I consider PMM interaction of a column in a zerolengt...
by hshoar
Fri Sep 06, 2013 9:18 pm
Forum: OpenSees.exe Users
Topic: Concept of ZeroLength Element
Replies: 3
Views: 720

Concept of ZeroLength Element

My problem concerns the physical concept of so called zero length element. suppose that we have a cantilever beam with a zero length element at its support like: ------------------------------------------ #units in cm, kgf model basic -ndm 2 -ndf 3 node 1 0 0 node 2 0 0 node 3 100 0 fix 1 1 1 1 unia...
by hshoar
Mon Sep 02, 2013 8:37 pm
Forum: OpenSees.exe Users
Topic: error in ststic analysis
Replies: 7
Views: 2189

Re: error in ststic analysis

when Opensees shuts down automatically usually it means that you have an obvious mistake in defining of your model! for example defining an element between two nodes which are not exist...
I think you will find the problem if you check it precisely!
by hshoar
Tue Aug 20, 2013 8:52 am
Forum: OpenSees.exe Users
Topic: deformation or displacement of a section
Replies: 1
Views: 332

deformation or displacement of a section

I need the rotational deformation of zero length elements at end points of beams in my model where I have put Zero Length elements. To do so, I plan to record nodal displacements of ends of every zero length element and then subtract them from each other to obtain the deformation. But, I have come a...
by hshoar
Thu Aug 08, 2013 1:49 am
Forum: OpenSees.exe Users
Topic: Nonlinear Hinge Definition
Replies: 4
Views: 1048

Re: Nonlinear Hinge Definition

I don't know what exactly going to happen during the analysis, but, I have to analyze the frame just under this load combination: DL + 0.25LL and then a column will be removed suddenly during the analysis. in progressive collapse guidelines it defines material as I mentioned in previous posts but I ...
by hshoar
Wed Jul 31, 2013 9:31 am
Forum: OpenSees.exe Users
Topic: Nonlinear Hinge Definition
Replies: 4
Views: 1048

Re: Nonlinear Hinge Definition

I am doing nonlinear dynamic analysis of a steel structure under progressive collapse. I need to use a specific material for zerolength element which defines Hysteretic behavior of plastic hinges with the following backbone force-deformation curve: http://dc432.4shared.com/doc/fLbdHG97/preview_html_...
by hshoar
Tue Jul 30, 2013 6:15 am
Forum: OpenSees.exe Users
Topic: Nonlinear Hinge Definition
Replies: 4
Views: 1048

Nonlinear Hinge Definition

In order to perform a nonlinear analysis I have to define nonlinear hinges regarding codes FEMA or UFC... As far as I know those properties have been represented in a force-deformation diagram: http://buildingcriteria2.tpub.com/ufc_4_023_03/ufc_4_023_030126im.jpg I need to know how I can model a zer...
by hshoar
Thu Jul 25, 2013 9:33 am
Forum: OpenSees.exe Users
Topic: Dynamic analysis not under seismic loads!
Replies: 1
Views: 307

Dynamic analysis not under seismic loads!

I want to model a 2D elastic cantilever beam which is subjected to a time dependent transverse load at its free end defined by f(t)=1000t (0<= t <=0.1s), and I am looking for displacement time history of the free end during t=0~50 sec, but, I could not find any examples or manuals explaining the pro...
by hshoar
Fri May 10, 2013 6:39 am
Forum: OpenSees.exe Users
Topic: integrator LoadControl
Replies: 3
Views: 1290

timeSeries

According to what I have understood, load factor is calculated with respect to time through different options of timeSeries Object. What I don't understand are: 1)Is there any relation between time steps in timeSeries and number of steps in analyze command? 2)What exactly are number of steps in anal...
by hshoar
Fri May 03, 2013 8:53 am
Forum: OpenSees.exe Users
Topic: integrator LoadControl
Replies: 3
Views: 1290

integrator LoadControl

I have some problem with "integrator LoadControl" command and can't find any informative explanation from the web about what the command exactly does. Regarding manuals this command is used for three specific items which confuse me more. I am doing a nonlinear static analysis for a 2D portal frame s...