Double fillet welded corner joint

Dear weh

The weld you shown in that sketch was good and economical compared to full welding in corner.
this type of welding is available in AWS. please refer

I would say that the connection details depend on the magnitude of the load and whether the nature of the loading is static or cyclic.

In the case of static loading, as long as the fillets are sized properly, they should work. However, if the loads are cyclic, the unfused root can act as a crack initiation point.

The Engineer, responsible for the design, should be the individual making the decision whether the connection is appropriate for the application.

Best regards - Al

The weld, top left, should be a sixteenth of an inch thinner than the thickness of the top plate; as shown, it looks more like full penetration depending on the difference in plate thickness.

Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin

The loads are static. If the plate is greater than 1/4" than the welds would be a minimum of 1/16" less than the plate thickness as per sect. J2 of the AISC Steel Construction Manual.

Two thoughts. First that wouldn't be my favorite weld configuration due to joint prep. I imagine there would be a lot of open root welding going on. That being said to say a weld is not code approved-I dunno. If one developed a wps for a specific configuration and qualified it, assuming it met prescriptive criteria, I believe you could meet aws.

I was on a job where a double fillet was said to be equivalent to a full pen. It would have been except we were using grade 60 572 plate instead of 50 which the fillets were sized for. Also it was composite wall construction so the plate was acting as rebar and had to be able to develop loads beyond yield. Bottom line is the numbers didn't work out and they cut out/ground out a few thousand feet of fillet weld, beveled the plate for a full pen and used the back fillet as backer bar. Now that was a crazy weld but it was qualified and a wps created and we had welding engineers on the engineering and contractor side looking at it. This was on a nuclear power plant so obviously the budget was large, just pointing out that odd weld joints have been used in the past.