Non-Standard Structural Shapes 3

[msquared48]

Does anyone have a link they can post to a simple program they have used in the past, or know of, to generate section properties for odd, non-standard structural shapes?

The one I have is a series of bent plates of various lengths and thicknesses with interior bend angles not 45 degrees.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[ToadJones]

Use CAD if you have it.

 

[msquared48]

Sorry, I meant "but not 90 degrees", as in angles.



Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[msquared48]

Talked to the CADD guy and he said no for the S and I values, which is what I need to generate, along with Ixy too

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[sbisteel]

The command is "MASSPROP" in AutoCAD; you have to create a region of the shape and move its centroid to 0,0 in the drawing to get the appropriate moments of inertia. Once you have I, calculating c is pretty simple.

 

[jorton]

I typically use sigma-x for complex cross sections and difficult properties. It is not difficult to use, but it may be overkill for what you need. It is not free either.

 

[msquared48]

I'll let him know this. Thanks.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[ToadJones]

CAD will give you anything you need....may have to calculate things from what it gives you

 

[RWW0002]

STAAD V8i has a "Section Wizzard" under the tools menu from which you can build various custom shapes out of plate or standard sections. It will then compute all section properties. I have used it sucessfully in the past. It is obvoiusly not worth buying STAAD for, but if you are a STAAD user anyway, it can be usefull. (These custom shapes can also be imported into a standard staad model for analysis)

 

[Gumpmaster]

I use a program for this quite often. ShapeBuilder by IES. It's very flexible. It will give you plastic as well as elastic properties. It will give you torsional properties (J and such).

One of the nice features is that it has all of the AISC shapes built in so you can build composite members.

You can also apply a load to your composite shape and see the actual stresses in the shape (rather than just the idealized stresses).

Two thumbs up for both flexibility and ease of use. Far better than the STAAD or SAP versions.

 

[jimstructures]

I also use Shapebuilder from IES and find it relatively easy to use. It has AISC, AISI, Cold-form, Engineered Lumber, Concrete sections and many others in its library. You can download a fully functional version and use it for 30 days at

http://www.iesweb.com.

It does have a learning curve but it is accessible.

Hope this helps.

Jim

 

[msquared48]

Thanks. I have used this in the past and downloaded the trial version again. Worked. Just took a while to figure it out.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[slickdeals]

You can try Tomanovich's spreadsheet or Yakpol's. You will need to painstakingly input the coordinates, but it spits out everything else.

 

[kingnero]

google for "sectprop.xls"

 

[GregLocock]

Torsional properties of thin walled sections are best established using FEA, since there is no analytical procedure of unchallengeable accuracy for general shapes. For nicely symmetric tubes of regular shape there are analytical solutions. Unless you know how your CAD is calculating the torsionals regard it with a pinch of salt. A quick test is to compare the value it gives for a thin walled tube and a thin walled tube with a slit in it. The ratio of torsional constant should be around two orders of magnitude.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[StructSEZ]

Try ProSec in the Prokon software suite.

Cheers

 

[IFRs]

http://www.cadreanalytic.com/profiler.htm

 

[msquared48]

Shapebuilder works great. Already used it on two projects.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[johnbridge231]

You can have a look at this program as well.
Apart from cross section properties, it performs other calculations on cross sections of any material, such as moment vs. curvature plots, interaction diagrams, reinforcement design etc.

Regards.