Tubular column-girder ring stiffener design
Tubular column-girder ring stiffener design
(OP)
Anyone have any reference material on how to design a ring stiffener for a girder welded to a tubular column, such as an offshore deck leg girder connection? Do you use Roark case 1?
PC Engineers has a small program but I want to see the basis for their calculations:
http://www.lanxun.com/pce/ring.htm
PC Engineers has a small program but I want to see the basis for their calculations:
http://www.lanxun.com/pce/ring.htm






RE: Tubular column-girder ring stiffener design
RE: Tubular column-girder ring stiffener design
External rings are preferable to internal diaphragms for ease of fabrication.
RE: Tubular column-girder ring stiffener design
RE: Tubular column-girder ring stiffener design
RE: Tubular column-girder ring stiffener design
As an approximation, maybe something like this:
The job of the stiffener is basically to safely transfer the axial loads from the girder flanges to the portions of the tube that your considering to act as the "webs". I dunno, maybe 1/3 of the depth of the tube on either side? Maybe you could design the ring stiffener as a laterally braced, simply supported, semicircular beam? The stiffners could have there own stiffeners if necessary to justify the assumption of lateral bracing. I think that this would be most appropriate for a stiffener that isn't too wide relative to the diameter of your tube.
RE: Tubular column-girder ring stiffener design
The black AISC Design of HSS connections
and
Blodgett Design of Tubular Structures
(there is also another similar one)
Both are good in their own way.
RE: Tubular column-girder ring stiffener design
You may still generate some kind of partially parametrically driven model by modeling a cylinder in RISA 3D, for it admits both speedily change in thickness and dimensions, for you can scale within RISA itself the x, y and z dimensions separately. The loading shape, may need to be adjusted, however. Obviously, the plate segments will be plane in RISA and some of the advantages and problems generated by the fact of the initial shape being truly cylindrical won't be captured.
The release 2010 of autocad also allows parametrical design of blocks. I may try to generate a block like this just as a learning exercise, for it is a new feature, and one that will speed up the generation of structural models of this small complexity. At least the initial shape will be perfect, this way.
RE: Tubular column-girder ring stiffener design
By tubular, do you mean square or round?
RE: Tubular column-girder ring stiffener design
Round Sections.
Are you talking about Blodgetts Design of Welded Structures? I can't find a Tubular Structures Book.
Is the AISC book only rectangular?