Search found 29 matches

by geoStru
Tue Dec 01, 2020 11:01 am
Forum: OpenSees.exe Users
Topic: Infinite stifness axial for beam
Replies: 0
Views: 9

Infinite stifness axial for beam

Hello everyone, is it possible apply an infinite stifness axial to the beam? I used the rigid diaphragm on a RC 3D frame but the axial force on the beams isn't 0. And the yeld moment increase by axial force as for the columns. For the beams I used nonlinearbeamcolumn element. I tryed to apply this e...
by geoStru
Fri Oct 02, 2020 9:06 am
Forum: OpenSees.exe Users
Topic: Recorders for Moment-Curvature of columns of 3D RC frame
Replies: 14
Views: 615

Re: Recorders for Moment-Curvature of columns of 3D RC frame

Dear selimgunay and mhscott, during my thesis I should run many parametric analysis to study the ductility of global structure and the elements (columns). The behavior of concrete is correct. If I put, for the Steel02, minmax to 0.0675 (for the def) a lot of analysis didn't converge. In the other wa...
by geoStru
Wed Sep 23, 2020 11:46 am
Forum: OpenSees.exe Users
Topic: Assign frames releases
Replies: 2
Views: 241

Assign frames releases

Hello everyone,
For assign frames releases (joint beam/column) how could I do?
I want assign a hinge joint about connection of the elements beam and column (for example, to obtain M3=0 at the end of the beams)
I tryed with fix $nodetag but I think it is wrong.
I appreciate your help
by geoStru
Thu Sep 17, 2020 1:07 pm
Forum: OpenSees.exe Users
Topic: Push analysis doesn't converge
Replies: 34
Views: 1300

Re: Push analysis doesn't converge

yes I apply my forces to the master nodes, now I changed "variable maxNumIterStatic" 20 to 200 and it seems converge. sorry for the off topic but in general, when I try to run the analysis with the same model, sometimes they don't converge (only a few parameters like the angle of the push-forces or ...
by geoStru
Thu Sep 17, 2020 11:32 am
Forum: OpenSees.exe Users
Topic: Push analysis doesn't converge
Replies: 34
Views: 1300

Re: Push analysis doesn't converge

Does it have a convergence issue right at the beginning of pushover? If it is somewhere in the following steps, you need to try other adaptive solution strategies than those given. Here is an example Dear selimgunay and mhscott, during my pushover analysis I got the convergence when I set like "con...
by geoStru
Tue Sep 15, 2020 6:19 am
Forum: OpenSees.exe Users
Topic: 3D RC frame with the Capacity Design
Replies: 5
Views: 298

Re: 3D RC frame with the Capacity Design

Yes, I know the proc for valuate the behavior of 3D RC frame with the capacity design. But, probabily, my professor would like to study the teoric "L" behavior of 3D RC frame and the reduction of ductility of columns with different eartquake angles. First I used nonlinearBeamColumn for the diffuse p...
by geoStru
Mon Sep 14, 2020 12:57 pm
Forum: OpenSees.exe Users
Topic: 3D RC frame with the Capacity Design
Replies: 5
Views: 298

3D RC frame with the Capacity Design

Hi everyone. If I would like to study (with the analysis pushover) the beahviour and ductility of 3D RC frame with the teoric model of "Capacity Design", should I build the beam with "element beamWithHinges"? In this type of element are Lpi and Lpj at the node i and j similar than nonlinearBeamColum...
by geoStru
Sun Sep 13, 2020 7:51 am
Forum: OpenSees.exe Users
Topic: Eigen Value Analysis
Replies: 12
Views: 471

Re: Eigen Value Analysis

In OpenSees I used nonlinearBeamColumn. Should I use the elasticBeamColumn to compare the results of the 2 models?
I didn't use hinge models in Sap
by geoStru
Sun Sep 13, 2020 2:44 am
Forum: OpenSees.exe Users
Topic: Eigen Value Analysis
Replies: 12
Views: 471

Re: Eigen Value Analysis

OpenSees treats load and mass separately. So, you have to add mass when you add load if you want OpenSees to do what you're describing in SAP. Can there be any differences of periods by SAP2000 and OpenSees (3/4%)? I am attaching the results: SAP2000: 0.453 0.414 0.380 0.127 0.120 OPENSEES: 0.435 0...
by geoStru
Thu Sep 10, 2020 11:36 am
Forum: OpenSeesPy
Topic: 3D visualitation with Openseespy
Replies: 1
Views: 208

3D visualitation with Openseespy

Hi everyone, I use python to import my 3d model that I built in Opensees.
Is it possible to visualize the first six modes of my structure?
by geoStru
Sun Sep 06, 2020 2:05 am
Forum: OpenSees.exe Users
Topic: Recorders for Moment-Curvature of columns of 3D RC frame
Replies: 14
Views: 615

Re: Recorders for Moment-Curvature of columns of 3D RC frame

With p-delta and increased axial force, moment-curvature would have a descending portion. You can compute the ultimate curvature as the curvature corresponding to a) ultimate strain of concrete, and b) fracture strain of the longitudinal reinforcement, whichever happens first. Infact I thought the ...
by geoStru
Sat Sep 05, 2020 10:32 am
Forum: OpenSees.exe Users
Topic: Recorders for Moment-Curvature of columns of 3D RC frame
Replies: 14
Views: 615

Re: Recorders for Moment-Curvature of columns of 3D RC frame

The steel strain hardens indefinitely, so you'll have to try wrapping the material with MinMax https://opensees.berkeley.edu/wiki/index.php/MinMax_Material #Steel02 set Fy [expr 450*$Nmm2]; #N/mm2 set Es [expr 200000*$Nmm2]; #N/mm2 set Bs 0.01; set R0 18; set cR1 0.925; set cR2 0.15; set IDSteel02 ...
by geoStru
Sat Sep 05, 2020 7:29 am
Forum: OpenSees.exe Users
Topic: Recorders for Moment-Curvature of columns of 3D RC frame
Replies: 14
Views: 615

Re: Recorders for Moment-Curvature of columns of 3D RC frame

Thank you for reply. The file -xml is very useful. Now I trying to get a curve M-ϑ but I couldn't be wrong The curve F-s of 3D RC frame seems right But the curve M-ϑ doesn't decrease and I don't get the collapse (I used concrete02 and steel02).WHy? I am attaching the link for the images https://driv...
by geoStru
Fri Sep 04, 2020 7:46 am
Forum: OpenSees.exe Users
Topic: nonlinearBeamColumn/dispBeamColumn
Replies: 7
Views: 286

Re: nonlinearBeamColumn/dispBeamColumn

If I would like to use $np=5 what could I do to converge the analysis? or it is no necessary
by geoStru
Fri Sep 04, 2020 6:38 am
Forum: OpenSees.exe Users
Topic: nonlinearBeamColumn/dispBeamColumn
Replies: 7
Views: 286

Re: nonlinearBeamColumn/dispBeamColumn

Is there much difference for the results if I use $np 3 instead $np 5 (np=numbers of point integration) for the nonlinearBeamColumn? I have got a small 3D structure, with columns=4.00 meters and beams=6.00 meters. When I changed the numbers of the story (2 story to 3 story) the analysis doesn't conv...