To weld an overlap of steel reinforcements in stead of using stirrups

[msesi]

Currently I'm supervising a culverts structures of various diameter(pipe and box culverts)The Contractor would like to weld the overlaps of the steel reinforcement instead of using stirrups to bind the overlaps.He has proposed to used an overlap of 10cm and use spot or full weld to joint the overlap.Type of reinforcement he is using is high yield steel bars.If I allow him to weld the overlaps,does it have an effect to the whole structure???

 

[Ron]

Perhaps I'm missing something in your description or terminology, but this is what I understand you want to do...

Your contractor wants to weld rebar splices instead of using lap splices. If your code allows it and he uses a qualified welding procedure then, yes, it can be done without detriment to the structure. It is not likely that your code will allow tack welding. It will likely require a particular length of quality weld in a particular profile.

Check your code requirements first.

 

[hokie66]

As Ron noted, welding can be an acceptable means of developing reinforcing splices, but it has to be done correctly. Other means are lapped splices and mechanical splices. Your use of the term "stirrups" is confusing, as stirrups are transverse reinforcing.

 

[msquared48]

Is 20 cm max of weld enough to develop the full tension force in the bars?

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[msesi]

Thanks Hokie66 for your reply.Well the term stirrups Imean a very small wire of 1.6mm or 1.25mm in diameter used to tie one piece of reinforcement end to another end by providing apropriate overlaps.

 

[Ron]

msesi...a stirrup is a particular type of reinforcing. What you described is a tie wire, which is what I thought you meant. Check your code.

 

[hokie66]

msesi,
Not to be uncharitable, but it sounds like you have very limited experience with reinforcement. The tie wire has no effect on development of the bars, it just keeps them in place. To evaluate welding rather than lap splicing for development, you need a greater depth of knowledge about welding and reinforcing steel.

 

[msquared48]

To further what Hokie so diplomatically said, you need to seek the professional services of a structural engineer, or better yet, be one.

By the way, the contractor is not a structural engineer.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[rajutvvm08]

what is the minimum overlap length to weld a 12 mm hysd steel bar

 

[ishvaaag]

a 12 mm rebar must be well developed with maybe 2 inches of weld of akin strength each "side" and throats about 1/8"

Note that for the thing be aceptable the rebar must be of the weldable category, and not all are.

sd usually is added to specs most weldable, anyway.