Solid steel section made from steel plates
Solid steel section made from steel plates
(OP)
Hello everyone!
I wonder what's your opinion about welding thick plates in order to make a solid section (e.g. five 20"x 4" plates welded together --> 20" x 20" solid steel section)? Should the welds be CJP's or can be partial penetration groove welds?
I wonder what's your opinion about welding thick plates in order to make a solid section (e.g. five 20"x 4" plates welded together --> 20" x 20" solid steel section)? Should the welds be CJP's or can be partial penetration groove welds?






RE: Solid steel section made from steel plates
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Solid steel section made from steel plates
RE: Solid steel section made from steel plates
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Solid steel section made from steel plates
RE: Solid steel section made from steel plates
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Solid steel section made from steel plates
BA
RE: Solid steel section made from steel plates
A normal wide flange has 3x plates
A normal square hollow box has 4x plates.
A normal 5x plates has ????
(Will you make a WF shape, then weld 2x more end plates across flange end to flange end, welding only from the outside with a V-prep? )
Would you gain any resistance if you filled the hollows with concrete?
RE: Solid steel section made from steel plates
Then it's a wide flange with cover plates, not a solid section. Thornton Tomasetti successfully implemented this approach (solid steel columns) in The NY Times Building and Chicago Spire. In NYT Bldg they create 30x30" solid columns made out of five 6 inch plates welded together. Filling with concrete don't give so much extra capacity and moreover you gotta take care of differential axial shortening...
RE: Solid steel section made from steel plates
1) Heavy welding at the ends of the column to get the load in and out from the various plies quickly.
2) light welds or even bolts between column ends to ensure composite buckling. I'd minimize weld size as much as possible then, if it made sense, I'd look at stitch welding.
Another approach could be to make every second ply an inch or two narrower than the others. That might allow fillet welds to be used and avoid the need for costly surface prep.
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Solid steel section made from steel plates
I found some MEng project (Chicago Spire) done under supervision of Thornton Tomasetti's Engineers and look what they propose:
RE: Solid steel section made from steel plates
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Solid steel section made from steel plates
BA
RE: Solid steel section made from steel plates
RE: Solid steel section made from steel plates
RE: Solid steel section made from steel plates
Obviously, you don’t have a normal flange to web welding situation in the last set of sketches you have shown, or with material which is that thick. You are not trying to tie parts together the way we might in building up a normal WF or box shape. But, you must account for any shear flow which might occur btwn. the various parts and you must pay attention to individual pl. buckling, as well as total section buckling, where shear flow comes back into play. Then, you will have some special welding considerations w.r.t. AWS and AISC and min./max. weld sizes vs. plate thickness. Actually this is really a heat input issue, so that the large heat sinks/plates don’t cool the weld so quickly that it cracks or causes inferior HAZ’s. That means pre and post weld heating to the proper temps. and time durations. Then, you have an AISC ‘end bearing’ issue, you must end mill these types of heavy sections for good bearing. Finally, I can imagine some load transfer problems when sections or individual plates change sizes and locations; end splices will be complicated. I don’t think much of this requires full pen. welds, just imagine what a night mare that would be, in terms of prep. and weld costs and in terms of final section deformation from welding. Butt splices (in compression) btwn. pieces of pl. probably do need full pen. welding, and pl. edge prep. will be critical for fit-up and welding. You would weld something like this section from the middle outward, with much welding automation, repositioning for welding and deformation control.
RE: Solid steel section made from steel plates
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Solid steel section made from steel plates
RE: Solid steel section made from steel plates
Is this a pricing exercise where there will eventually be a "right" answer that you can share with us?
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.