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I wish I could have time to do a simple least square projection. But if I do need it later, I think I will code it and let you guys know.

I did analyses of solids using only the Brick element, and no fibers of section are involved. My primary interest now is to ouput the nodal stress for post-processing. For example, if knowing the stress on the nodes, I can easily generate smooth stress plot in Tecpot. I hope what I said is clear eno...

The element stresses and gauss point stresses can be recorded in OpenSees easily. But when I was thinking to ouput the nodal stresses, I don't know how to do. Has anyone done the nodal stress recording before? Any suggestion? I think I knew the nodal stresses can be calculated by certain projection ...

I got the CenterDifferenceNoDamping method right immediately after I use the diagonal SOE. And better when I change my element routine to give lumped diagonal mass matrix. After I did some debugging, I found the integration orders I used is just not high enough for correct consistent mass matrix. No...

Hi, Frank You reponse make things more clear now. Thanks. I did do some tests on the central difference(CD) methods, however no luck. I checked the CD code, and still not very clear how the RHS of the SOE was formed since it is different than what I expected. I think I will dig deeper into the code ...

Any comments?

Hi, Recently I developed a user element and some material models with OpenSee. And the codes work well in static analysis, dynamical analysis with Newmark method. However, when I try to use explicit methods for dynamical analysis, such as CentralDifference, HHT, ect. , my analysis quickly blows out ...

Thanks. That helps a lot.

Any response? Are these qustions too simple?
I can hardly find examples that use incremental displacement boundary condtions. Can anyone point out some?

Alex

Hi, I modified the exmaple1.tcl to impose a displacement in x direction on node 3, which is previously fixed in the example. And I changed the constraint handler to penalty accordingly, whereas the transformation handler just crashes the program. But the results I got is just garbage, can you help m...

Hi, developers I am recently looking into OpenSees. OpenSees is such a big library with OO design. I have a concern on the simulation speed of OpenSees. How's the speed performance of it? I hope I won't see much sacrifice of simulation time on most problems. Have anyone done some comparative studies...