Strand7 FEA software for Reinforced Concrete or Steel buldings? 2

[amirmy]

Hello. I am currently in the process of evaluating FEA soft-wares specially Strand7. I worked with OpenSEES and SAP2000 to assess potential of RC and Steel buildings against progressive collapse. I need to prepare a research proposal using Strand7 FE program. I would appreciate hearing from current Strand7 users about the advantages and disadvantages of this program to modeling RC and Steel buildings(for which type of building is better to use) and its capabilities to model Nonlinear dynamic analysis. Thank you.

 

[IDS]

Strand7 will do a 3D non-linear time history analysis, so should be able to tackle anything you can do in Opensees and/or SAP 2000. I find the interface easy to use (but I have been using it a long time). It has a reinforced concrete module available, but I don't know how good that would be at modelling hingeing behaviour. You can use your own moment-curvature tables though. It allows staged analysis, so you could for instance remove columns part way through an analysis. It also has a comprehensive API, so you can link it to external software. The only real disadvantage I see is that as a comprehensive general purpose program there is a lot to learn.

They have recently started publishing "web-notes", which are intended for licenced users, but I imagine your local supplier would be able to give you access to those related to seismic analysis.

Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/

 

[jhardy1]

As IDS says, Strand7 should be able to handle the non-linear transient analysis that you are looking at. Just make sure that you are buying all of the specific modules that you will need - the core package comes with a lot of capability, but there are some "high-end" features that are "optional extras" - e.g. the API can be very useful if you are doing parametric studies, as it allows you to "drive" Strand7 from a spreadsheet or other programmed interface, so that you can adjust model parameters in your spreadsheet, and automatically run the solver and import and summarise the results from a customised user interface.

The Reinforced Concrete module is aimed more at post-processing plate / shell element results for design of reinforced concrete slabs (not beams and columns), but doesn't really affect the analysis phase - it is just a specialised post-processor.

Once you have a legitimate licence, you should get access to the Web Notes and the Verification Manual (and sample problems), which can be invaluable aids in setting up complex analyses, particularly if you need to use new modelling / analysis techniques that you have not used previously.

Let us know if you have any specific questions as to the capabilities of the program, and we'll try to help.

http://julianh72.blogspot.com

 

[amirmy]

Thank you very much for the precious comments. based on your experiences, It is better and easier to use for RC or Steel buildings? Thank you.

 

[amirmy]

Dear IDS and dear jhardy1, i mean considering all aspects of modeling, modeling and conducting nonlinear dynamic analysis of which type of building(RC or Steel) is easier and friendlier. Because i need to prepare a research proposal using this software and my concern is problems may i face in the future. Which type of building do you recommend to modeling using this software?

 

[IDS]

I really don't think the software has got much to do with which material you investigate. I work mainly in concrete, and not in building structures, but I would think that steel would be easier to model because its non-linear behaviour is more predictable, but that would apply in any software. Strand7 has libraries of standard steel sections, if that's important to you.

But surely the priorities of the people providing the funding are more important?

Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/

 

[jhardy1]

It's not the material choice that determines the simplicity / complexity of modelling, it's got more to do with the complexity of the geometry, and the type and purpose of the analysis to be undertaken - and this will be true for any analysis package. (Strand7 comes pre-loaded with material properties for a range of both steel and concrete.)

The simplest thing to model in Strand7 would probably be a simply-supported beam with a UDL or point-load at midspan. Steel can be "simpler" to model than concrete (if you are not going into plastic deformation etc), because it conforms quite well to a classical linearly-elastic material model, but you may need to model non-linear materials even for a simple beam if you are looking at plastic hinge formation, etc.

(The most "complicated" thing I have ever modelled in Strand7 was also a steel structure - a fire-damaged pressure vessel, for which I needed to model significant initial geometric imperfections due to previous fire damage buckling the shell, non-linear P-delta behaviour, tension stiffening, temperature-dependent material properties, and time-dependent loading and material properties. This took weeks to build the model, and the run-times were several days per run for the final model!)

http://julianh72.blogspot.com