The OpenSees Community

Thanks...

I've a colleague who's trying to register. There's a test question with 3 answers that he can't get past. He's tried all 3 (I guessed concrete shell), but keeps getting an invalid answer response. Please advise. Thanks... Confirmation of Registration Identify element types that might appear in a str...

Hi, I'm trying to learn how the eleResponse command works. The documentation says that the arguments for the command are: "$arg1, $arg2 same arguments as those specified in element recorder. These arguments are specific to the type of element being used." Going to the element Recorder docu...

Hi Ernesto, After several hours of poking around I think I finally figured it out. Download Tortoise snv onto your computer, go to this link; http://opensees.berkeley.edu/wiki/index.php/OpenSees_Developer and then click on the link supplied at the bottom of the page; svn://opensees.berkeley.edu/usr/...

I have had exact same question for a while now, can .C and .H files be downloaded from the svn repository? I followed the link supplied in the response to the download section, it didn't work for the latest version, and, I'm not even sure that's what I want, I don't want the whole OPENSEES code, the...

Hi, I'm having trouble compiling a new material, and was thinking that one reason may be that the support files I have may be obselete. Frank's presentation included the instruction to import the files from the "core" folder into the project. The core folder files I have are a couple of ye...

Hi Silvia,

What type of isolator? I've used a viscous damper + hystereric material + spring in parallel to model sliding PTFE with restoring force type isolators.

Paul

For beam problems, lump 1/2 the element mass at each of its nodes. Assuming the eigenvectors are mass normalized, multiply the eigenvector displacement for the direction of interest times the nodal mass. Sum all these products up to yield the participation factor. For plates and solids a good FEA te...

I'd start using both programs if you have access to both. Both can provide different insights, act as checks, and as your project evolves the question of when to use which program will surface naturally...

PB

Thanks for the feedback Frank/Silvia. I agree Silvia, this sort of thing almost always turns out to be model error, I just haven't been able to find it (yet). And given I've noted what seem to me rigid element anomolies in the past, and that I've had mixed success matching OpenSees modes with those ...

Hi, On a few projects now I've been getting unexpected modal analysis behavior at rigid type connections (rigidLink and equalDof). For example, I've two perpindicular lines of nodes joined as a T. On the vertical line are elastic beam elements, the horizontal nodes are slaved to the intersection nod...

1 - Thanks Sylvia and Frank, much appreciated... 2 - Gentlemen commented on the need node lists. I agree. I thought Frank mentioned that node queries are available in 2.1, but I can't seem to find the message referring to that function. 3 - Suggested functionality - provide access to matricies (glob...

Hi Sylvia,

Do you know if we'll be able to receive PDH credits for attending?

Thanks,

Paul Bradford

Hi, Section 4 "Adding New Element to OpenSees" in the OpenSees Dynamic API document says that "an element is responsible for determining its tangent and resisting force given the changes in response at its nodes." The element I'm working is velocity dependent. Does OpenSees need ...

I'm with you on this on go. That's basically the same request I had. OpenSees 2.1 allows users to write their own elements, I think coupling could be done with this capability. I'm writing a bidirectional zerolength isolator element now, but won't be done until May.