Re: AISC 360-05 Table J3.4 1

[Wburger14]

Steel newbie here--
How is structural steel plate (say 1.25" thk, plan dimensions are ~48"l by 9"w) typically cut? Looking for the method (saw, plasma, laser, others?).

and following on the first Q:
Referring to the middle column of Table J3.4, what cutting methods constitute a "Sheared Edge" condition?
Obviously, thermal cutting is covered in the rightmost column. So, is anything without a rolled edge or cut using a thermal cutting process considered a "sheared edge" (in other words, could the heading of the middle column be changed to "all other edge conditions" or similar?)

 

[nutte]

I don't think plates that thick are sheared, but I'd wait for someone who's more knowledgable to respond.

For the second question, I've always thought of the third column as the "all other conditions" method. I would put a saw-cut edge in that column.

 

[WillisV]

Sheared edges just mean that the piece was cut by basically ripping it apart instead of thermal or saw cutting. Generally plates less than 1” can be sheared off – thicker plates and rolled shapes (channels and I beams) are rarely sheared due to the force required. See

http://www.thefabricator.com/articl...he-sheer-facts-of-shear-tooling-and-processes

 

[ToadJones]

Almost all Fab shops use plate burning tables; either gas or plasma for cutting plates. From my experience, thinner plates, say 1/2" and below are sometimes sheared if they are simple shapes. With CNC operated equipment these days, most parts are thermally cut directly from CAD drawings of the details.

 

[connectegr]

For most fabricators 3/4" is the max for a shear press.

For 1 1/4" PL the plate is probably gas cut (maybe plasma). 1 1/4" is a little thick for plasma cutting.

No "cutting" method would apply to a sheared edge.

I believe with improvements in the shearing equipment, the middle column will eventually disappear from the spec. (just a rumor)

 

[WillisV]

Connectegr - correct - that line of the table has been removed in the forthcoming 2010 Specification. No more differentiation between sheared and cut edge distances. Also an absolute minimum of 1 bolt diameter has been added for edges not in the direction of force.