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My apologies. Here is a quick code I wrote to model a simple elastic beam with a point load. It is modelled twice, once using elasticBeamColumn Elements and the other with ShellMITC4 elements. The code includes an output showing the midspand and end moments in the BeamColumn element, my question is ...

Sorry to keep pestering a point, but does anyone have any ideas for my above problem?

Hi all, I'm confused about getting moments out of a shell element. I've run a test example to compare a simply support beam modelled either with a BeamColumn element or a series of shell elements and a point load in the middle. With the two cases I get almost identical deflections out and the BeamCo...

At the moment I'm modelling a steel frame by simply using elastic BeamColumn elements defined along their centre lines connected by simple nodes at the intersection. However since I'm using very large sections the frame has very low span to depth ratios I'm wondering how accurate this approach is. S...

Is there an element that can consider the geometric nonlinear effects of beams at high deflections? In particular I want to know if catenary action is forming.
I would have thought using a fibre section element could do this, but I'm not sure from my results.

Thanks for your help.

To locate a file just specify the path to it. In your case you can use:

[open results/disp.out r]

usual rules for variable substitution exist so if you have a long path name or want to open different folders in a loop and such can use:

[open $path/disp r]

I would use the path time series command.

http://opensees.berkeley.edu/wiki/index ... TimeSeries

you can use a standard script for writing to a file set modeMassFile [open "Modal Masses.txt" a]; # Creates a new file called "Modal Masses.txt" sets it ready for writing and links it to a variable puts $modeMassFile $modalmasses; # Writes $modamasses to the file close $modeMassF...

If I understand your problem and you want to run the analysis until a certain nodal reaction then you can use a script similar to this: set reaction 0 set reactionLimit 100 while {$reaction <= $reactionLimit} { analyze 1 set reaction [nodeResponse $nodeTag $dof 6]; # The 6 is the ID for nodal reacti...

the recorder command only writes the data to a file after the analysis is finished when either a wipe or exit command is given. If you want the results during the analysis then you can use the eleResponse command. http://opensees.berkeley.edu/wiki/index.php/EleResponse_Command This gives the results...

I won't be able to make the event, however, will information from it such as presentations be made available online afterwards?

If you want to know the time taken to evaluate a section of code you can use the time command time { # Enter code here } $count; If you specify a number here it will run the above code that many times and average result. Default is 1. Alternatively a better method for bigger projects is to compare t...

Thanks for the reply. Shell elements should be OK, at least for what I'm doing for the moment. However I've now hit another error using the block2D command. Do you have to explicitly state the co-ordinates for each of the boundary node points or can you use a previously defined variable? For example...

Sorry to keep pressing this but can anyone explain whats wrong with my above code?

Thanks

Thanks for those answers. However I've just tried to use Quad elements in 3D as you described but I still get the same error about dimensions and/or DOF not compatible with quad elements. My trial code is below. Is there something missing or wrongly defined then? # 3 Dimensional Quad Test wipe model...