Structural Stell Connection At The Web

[LIGWY]

I have a W10x33 Column The Web thickness is 0.29. I need to assure that when I attach a jib crane with a 30' span to hold 1/2 ton. in the web section it will not pull out the web. I am using a manufactured jib that the Thrust & Pull is 6020#. I can not seem to find the formulas for this so I can check it. My gut feeling says I need to add a plate to thicken up the area of connection.

 

[ronstruc]

Probably a good idea to strengthen the web. I think you could you could check the web by calculating the bending moment and figuring the required section and then check it with the section of the web.

 

[jike]

I think it would be advisable to add stiffener plates, welded to the web and the flanges. Design stiffener plate to span between flanges to carry the load.

If you want to analyze it, you probably would need to use "Yield Line" theory.

 

[LIGWY]

jike,

Do you mean such as a bearing stiffeners?

 

[LIGWY]

Because I thought you would use a flange to flange (perpendicular) to the web would be used if th jib was connected to the flange not the web. OR do I just misunderstand this concept.

 

[jike]

Yes, that is one idea. Also, another idea is to add a web doubler plate.

Just a question.... most jibs that I have seen are attached to a column flange so that they can swing approx. 180 degrees. Attaching to the web would limit the swing quite a bit. Are you sure this is what you want to do?

 

[LIGWY]

Yes because of the area there is not enough room on the flange to reach the equipment!

Thanks, I guess I needed reassurance

 

[LIGWY]

A web doubler plate is parellel with the web? Just to make sure I am picturing this I have done several flange to flange but as I said this is connecting the jib on the flange because I believe that YES it is better for swing

 

[Redfish205]

Why not weld a "tee" into web of the W10 column made of two plates (or a piece of Wide flange). Then attach to the flange of the tee. This would give you the full 180 degree swing and the flange portion of the tee could be welded to the W10 flanges. Easier welding than a doubler plate.

 

[jopalu]

Redfish205,

Depending on the length of the tee, whether it be one or two piece, welding the web of "tee" to the web of W10x33 could be difficult...

Regardless of the weld process, you do not have a direct, acceptable angle approach to obtain a good fillet - you have to approach the weld surfaces on a skew. Please correct me if I am misunderstanding something ...

 

[Redfish205]

Jopalu
I think you are understanding everything correctly. I agree, if the tee is extremely long, the weld would be a problem. We have used this connection in other applications with no prolems or complaints from the fabricator provided the tee is no longer than about 18" or so. I don't know what kind of length Abutler is talking about for his jib connection though.