Intermittent Groove Welds

[NS4U]

Are intermittent groove welds prohibited by the code? If they are not, what is the minimum length that can be considered effective?

AISC and AWS are awfully silent on this issue

 

[Bagman2524]

You might want the try the welding forum.

 

[HgTX]

"the code"? Which code? What is specified in the contract or local regulations?

Hg

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[NS4U]

.... AISC and AWS ....

 

[HgTX]

AWS what? There are a lot of AWS codes. I can see 7 different ones from where I'm sitting.

Hg

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[NS4U]

D1.1....

 

[JLNJ]

I would need to dig out AWS D1.1 to answer correctly, but I try to keep the minimum length to 1 1/2" for a 3/16" weld just to be practical. I'm going to guess that the minimum is in the range of 6x weld size.

 

[nutte]

NS4U,

I was also wondering about this. I have the 1990 version of AWS D1.1, and it says in section 9.12.3:

Intermittent groove welds are prohibited.

Chapter 9 deals with Dynamically Loaded Structures. The commentary says that these welds, along with others prohibited by 9.12, do not perform well under cyclic loading. It goes on to say that "the prohibitions do not apply to welds in those secondary members which are not subject to cyclic stresses."

So, they're prohibited in dynamically loaded structures, except for secondary members with no cyclic loading, where they would be permitted. Presumably they're permitted for any member in a statically loaded structure. As far as minimum lengths, I suppose you're on your own.

 

[NS4U]

I searched this website and something came up that said the Chapter 2 of the 2000 edition said that intermittent groove welds are prohibited, however I see no reference to this in the 2008 version. I'm wondering why it was removed between 2000 and 2008, or if it was just moved.

 

[NS4U]

Looks like D1.1, 2.7.4 allowes intermittent PJP welds, but prohibits intermittent CJP welds. It does not provide any guidance on effective lengths, though. Unless I am missing something?

 

[HgTX]

Effective length for groove welds is in D1.1 clause 2.3.1.1.

Hg


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[NS4U]

I agree, but why doesn't the same logic that requires the the 4t minimum length for fillet welds apply to groove welds?

I mean, you still need to build up the thickness of a groove like you would a fillet, unless you're required to use some other means such as a "side backing"?

 

[nutte]

Hg or NS4U, can one of you elaborate on what clause 2.3.1.1 says?

 

[NS4U]

Essentially:
"the effecitve groove weld length is the length of the groove weld"