Model custom shape

[McSEpllc]

Hi Everyone,

I am working on an 1952 building in which there are existing open web steel joists to be shortened. The existing open web steel joists have a custom top and bottom chord in a WT-configuration. The top and bottom chords are made of the 1/8" (deep) x 3 3/8" (wide)flange with a 3/8" (wide) x 3/4" (high) stem. Is there a way to model this custom shape in RISA?

Thanks Guys!

Eric McDonald, PE
McDonald Structural Engineering, PLLC

 

[Lomarandil]

RISA section will create custom geometry shapes for you (as I understand it, haven't used it myself)

If you have another way of obtaining the section properties (hand calcs, AutoCAD, shapebuilder, etc), you can import custom geometries into RISA. There are at least two ways to do this:

[ul]
[li]If you are only looking for design shears and moments, I find the easiest way to do this is with a custom section set -- manually enter the section A, Ix, Iy, and J. That's all the finite element solution needs for analysis.[/li]
[li]If you want RISA to compute stresses for you, you'll need to build a custom shape with a few extra properties (primarily the depth to the extreme fibers in each direction).[/li]
[/ul]

Neither of these options will allow RISA to perform any design or code checks for you -- those would have to be post processed.

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The name is a long story -- just call me Lo.

 

[McSEpllc]

Thanks Lomarandil

Eric McDonald, PE
McDonald Structural Engineering, PLLC