Moment connection by full penetration weld

[SemiPE]

Hi all. I have 2 beams of the same size that will be supported by a girder (also same size). The beam on the right will have a moment due to cantilever action and the beam on the left will balance out that moment (because its other end is pinned). Will Full penetration weld be enough to constitute as a moment connection, to transfer the moment from one beam to another?

I would usually put the beam on top of the girder so that the beam would act like a continuous beam, but the architect would not let me do that.

 

[rowingengineer]

I would like a detail just to confirm the arrangement.

http://www.nceng.com.au/

"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning."

 

[hokie66]

Full penetration welding of the flanges, and fillet welding of the webs, would be an acceptable connection. But a bolted moment connection would be my preference, as it requires less supervision and inspection on site.

 

[rowingengineer]

Hokie,
I think that a girder separates the two beams, at this time I don't know the girder size, but I doubt this is going to be a simple arrangement of flanges and webs. but then again I could have read it wrong. I would really love a sketch.

http://www.nceng.com.au/

"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning."

 

[dik]

Can the cantilever portion be shop welded to the girder and the backspan beam be bolted?

Dik

 

[connectegr]

To be clear... Top of steel for all three beams is the same. Therefore the flanges are all aligned (theoretically). Yes, full penetration welds of the flanges of the cantilever beam and back-up will provide the moment capacity of the cantilever beam. The web connection to the girder needs to be for the shear only.

http://www.FerrellEngineering.com

Providing fabrication and erection efficient structural design of connections. Consulting services for structural welding and bolting.

 

[SemiPE]

Everyone thanks for your replies. Connectegr is correct in his assumption that all the beams have the same level, since they have same sizes. Here is my answer to your replies:

rowingengineer - steel size would be 203x203x46.1 kg/m for all beams. The full penetration weld will be at the flange of the beam to the flange of the supporting girder. Sorry I dont have a sketch.

hokie66 - I agree with you on the bolted connection, I also prefer bolted connections compared to welded connections due to quality issues especially on site welded steel members.

dik - The architect "prefers" not to see any bolting on the steel members.

connectegr - Thank you for your comment. Do i need to check the girder for any localize failure? ie tension/compression of the flanges? Do you have any good references when designing such a connection.

 

[connectegr]

I don't know enough information to offer definitive advise on the girder connections. In the simplest case the cantilever and backup beam are equal and opposite moment forces. Therefore the net effect on the girder is zero torsion and some vertical force only. The girder to column connections may be shear only.

http://www.FerrellEngineering.com

Providing fabrication and erection efficient structural design of connections. Consulting services for structural welding and bolting.

 

[hokie66]

What is it with these "modern" architects? What do they have against bolts?

 

[trilinga]

Will your architect allow to provide flange plates? If so, you can transfer the compression and tension from the flanges of the cantilever to the supporting beam on the other side by welding flange plates through the connection at the top and bottom. The web connection can be a shear connection. The only disadvontage is that the flange plates will project above (and below) the beam flanges.

Trilinga

 

[Ron]

hokie66...same thing they have against thinking.

 

[SemiPE]

hokie66 - Most of these modern architects like to use "smooth & curvy things" (somehow i am getting a hint where their design inspiration comes from)

Trilinga - I have tried bargaining with the flange plates, but the archi didnt allow it.

Ron - Sad thing is we have to live through it