There was a thread some months ago on this subject, I believe in the structural engineering portion, which I can't find now. Perhaps someone can direct you better than I can.
The summary of the thread as I remember was that the chemistry of the steel in rebar is not closed controlled, so welding can change the physical properties significantly, to the point of failure under load. Recommend tying the rebar as is customary. The discussion was split on cutting cold or with a torch, since the heat affected zones would only be at the very ends.
There is a good article on welding reinforcement bar in the Lincoln ‘Procedure Handbook Of Arc Welding’. This is huge book covering most common practical aspects of arc welding and more. Its dirt cheap, most respectable welding shops will have a copy lying around somewhere. It can be ordered in the USA via lincolns web site, I have the UK address if you need it.
Hi,
Have you been answered already?
I have the same problem. One idea is to heat the bar just before welding and of course it has to be weldable i.e. low carbon rebar.
Know any more?
Konoli
