End-Plate Web Weld

[BadgerPE]

Hello all,

Are there any limitations to weld thickness for fillet welds placed on two sides of a beam web for a end-plate moment connection? I haven't been able to find anything and we are joining AISC to get the Design Guides to verify the connection software that we are using. Currently the program is requiring 5/16" fillet welds on each side of a 0.3" web to develop web forces into the columns. Any thoughts? As a disclaimer, this is a preliminary design and I will have the proper literature in house before this design is finalized.

 

[ishvaaag]

As per EA-95 (outdated Spain's code) it seems a size a bit in excess for the thickness; the code has specific limits as well for welds on webs but no US shapes. Note that the table gives weld throats, not sizes.

 

[JoshPlumSE]

AISC Design Guide 4 states that you should size the weld to develop the web capacity in tension. They don't talk too much about why this is though.

I think the idea is that (for seismic applications) you expect the flanges to go past yield as your moment approaches Cpr*Ry*Mp. Therefore, you don't want any fracture to occur at the web weld.

For non-seismic applications you may be justified in ignoring this provision. After all, it's not included in Design Guide 16.

 

[connectegr]

The weld size is suspicious, but. As you mention, Design Guide 4 will provide more information on the design of these welds. Your program may be providing a "minimum" fillet weld size based on the thickness of the end plate. However, the thickness of the thinner material may be used to determine this welds size if low hydrogen process is used. This may be a setting in your program. ref. AWS Table 5.8

http://www.FerrellEngineering.com

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

 

[ishvaaag]

Just another opinion soon found in google

http://www.webcivil.com/uswelding.aspx

 

[BAretired]

I don't see any problem using 5/16" fillet weld on each side of a 0.3" thick web meeting an end plate. If it is needed to develop the web, I would use it.

A more common weld size would be 1/4" which would seem to be adequate to develop the yield strength of a 0.3" web having Fy of 50 ksi.

BA