Welding Rebars Together 2

[abusementpark]

A few slab to grade beam dowel bars were broken during construction operations. Is welding them back together an acceptable solution? These particular bars aren't very critical.

 

[Ron]

abusementpark... since you are in the US, you can weld rebar if appropriate procedure is followed. Follow AWS and ACI criteria.

 

[abusementpark]

Is there a certain procedure for welding broken rebar back together? I'd imagine there are specific preparation requirements. Not that I need it in the case, but can you develop full strength with a splice weld?

 

[asixth]

I do it all the time although I don't think it is completely acceptable. If they are shear bars I don't see it being too critical, for flexural reinforcement the correct precautions should be used. It has something to do with the type of electrode used and it is poorly managed in the field. Site welding is a trade and will be treated as such on-site. It is best to reduce the capacity of the reinforcement and redesign accordingly.

Welding reinforcement is different to welding mild steel plates.

 

[TLHS]

If it's not classed as weldable rebar I'd probably suggest that you use a mechanical splice.

 

[TXStructural]

AWS D1.4 is the welding code for reinforcing bars. If the bars are ASTM A615 (Canadian type S), there are significant preheat and cooling requirements. ASTM A706 (Canadian type W) is more easily weldable.

In the situation described, you will probably not be able to weld the bars in a way which would give them proper strength. Mechanical splices are probably a better solution in this case.

John Turner CSP PE
CRSI Greater Southwestern Regional Manager

 

[steellion]

Abusement, another alternative to your particular solution may be to epoxy in new bars and abandon the damaged bars. But I wouldn't weld bars that aren't specifically weldable rebar.