The OpenSees Community

selimgunay wrote:
> You need to use the reaction recorder. Please see the below link for the
> syntax
>
> recorder Node -file nodesD.out -time -node 1 2 3 4 -dof 1 2 recorder
>
> http://opensees.berkeley.edu/wiki/index ... e_Recorder

hi
this recorder am using already. I want the result on the opensees screen by using print command.
By using I get coordinates and everything. But how can i get only reaction?

gabrielvaldes wrote:
> zak and selim
> i have downloaded opensees navigator, now i can visualize my models
>
> thanks all of you for supporting me
> we will continue to make this community bigger

HI,
How to input the tcl code into Opensees Navigator and get the visualization?

hi
How can I print only reaction of particular node with particular dof?
Say for example, I need to print node 11 only horizontal reaction and then the obtained horizontal reaction I need to multiply with some factor.
Can you please provide some solution for it?
Thanks in advance

Hi
Can you provide any example how to provide both shear hinge and forceBeamColumn element and integrate them with section integrator?
It will be easy for me to understand by going through the example
Thank you

Hi
Did you find how to model shear hinge ?
Can you explain how it is done?

EricsonEncinaZ wrote:
> For elements with distributed plasticity, i.e. either force-based
> (http://opensees.berkeley.edu/wiki/index ... mn_Element)
> or displacement-based
> (http://opensees.berkeley.edu/wiki/index ... mn_Element)
> elements, you have to define the number of integration points (sections) as
> part of the definition of the element. This integrations point will be the
> sample point where the element will sample the demands to workout the
> element output (according to what I understand) . So if you want to see if
> a section is developing plastic strains then you have to record the
> response of that section, as in the example shown at the bottom here
> http://opensees.berkeley.edu/wiki/index ... t_Recorder.

Hi EricsonEncinaZ, Thanks for your reply. Am working on RC frame.
How many BC elements to be used for forceBC element and dispBC element? I had seen somenone writing 1 forceBC element is enough, where 4 to 5 dispBC elements are required to analyse a structure. But is that 1 forceBC element same of both beam and column elements? or is it different?
I had read that the file in Opensees wiki FBE VS DBE. From that I had got the information.
Can you please explain these lines which is given in that file:
"The force-based approach relies on the availability of an exact
equilibrium solution within the basic system of a beam-column
element. Equilibrium between element and section forces is exact,
which holds in the range of constitutive nonlinearity.
• Section forces are determined from the basic forces by interpolation
within the basic system.
- Interpolation comes from static equilibrium and provides constant
axial force and linear distribution of bending moment in the
absence of distributed element loads."

Thanks in advance

Hi EricsonEncinaZ,
Thanks for your reply.
I didn't get what you mean by read the integration points? Can you please explain a little bit further. Am new to opensees
Thanks in advance

Hi,
How to know the hinges location in Opensees while performing Pushover Analysis step by step?
In SAP2000, we get to know by color, since visualization is not possible in Opensees, is there any command for it to know the location point?

Hi,
I am performing pushover analysis for 2D RC frame.
1)Iam using for transformation command for defining elements as " geomTransf ColTransfType PDelta". Is it necessary to define the rest <-jntOffset $dXi $dYi $dXj $dYj> always?
2)When am using PDelta, am getting initial displacement values as negative values. Is it correct? If correct, how to make a graph with positive values by taking those negative displacement values and corresponding Base Shear values in the final plot?
Am showing an example of initial part of the results below:
Disp Base Shear
0.0062 0.0000
0.0130 0.0000
0.0144 0.0000
-0.0019 0.0000
-0.0534 0.0000
-0.1554 0.0000
-0.3134 0.0000
-0.4966 0.0000
-0.7037 0.0000
-1.1284 0.0000
-0.8284 1.3089
-0.5284 2.6195
-0.2284 3.9186
0.0716 5.2092
0.3716 6.4849

so here, the displacement value -0.2284 can I make it to zero, can I add the corresponding base shear value 3.9186 to the other base shear values and take it as final?
3) Is it necessary to do " geomTransf ColTransfType PDelta" for pushover analysis, or is it sufficient to do Linear ?

Thanks in advance

Hi,
How many dispBC to be used for matching with one forceBC element? I had the read the file FBE VS DBE and followed same, but am not getting results as such.
Also which element is better to use if one needs to compare with SAP2000 results?
Thanks in advance

EricsonEncinaZ wrote:
> If you are doing an elastic analysis it should not matter the number of
> nodes and elements, but if your analysis contains non-linearities (and
> depending on the type of elements and loads) meshing is quite important. If
> this is your case, this is the reason why you have different results. A
> meshing sensitivity analysis should be performed to determine the best
> meshing scheme that provides accurate results and it is not too
> computationally expensive.

HI,
How to perform meshing sensitivity analysis? And how to get the best meshing scheme?
CAn you help me with this
Thank you

How is it possible with disp based elements?

mohsenrock wrote:
> other parameters like integrator or ... should not be changed right?

Hi,
What is the use of integrator?
Are you able to resolve the issue with 4 beam elements?
In my case it didnt resolve the issue

mohsenrock wrote:
> Thanks a lot for your answer. I used a concrete material with a minimum
> value for tensile strength and it works.

Hi
are you getting same results for the different cases you have mentioned.
I have used 5 dispBC elements for representing one beam and run the pushover analysis. and also using forceBC element I had run the model.
In these two cases am getting different results? Can you help me with this that which element to be used for better results?
And also which steel material to be used for RC frame for better output? Is it steel01 or steel02 or reinforcing steel? Currently am using Reinforcingsteel
Thanks in advance

fmk wrote:
>
> http://opensees.berkeley.edu/wiki/index ... ed_Element

Hi,
I had read that file FBE VS DBE approach. I have modelled 2D single story RC frame using dispBC and forceBC elements for pushover analysis.
In fact I had subdivided each element into 5 elements for dispBC element, by that am getting Baseshear =52 KN and corresponding displacement as 57mm
and by using forceBC element am getting Baseshear= 41 KN and corresponding displacement as 36mm.
It is a huge variation in the results. Now am confused which element to be used for my further analysis.
I have to do pushover analysis for 3, 4 , 5 ,7 story RC frames, so I would like to know which element is preferred for Pushover analysis? and if dispBC is to be used how many divisions(meshing) to be done for getting better results?
Thanks in adavnce