reuse of rebar

huangyhg

reuse of rebar
is it possible to reuse rebar?  for example, lets say i have an existing flat structural one way concrete slab 12 inches think.  a 12" ramp needs to be built in to it.  can i remove the concrete around the rebar, cut them to the required lap length, and bend them down to the ramp slope, and pour new concrete on the sloped ramp portion?  are there issues with bonding the new concrete to the existing rebar?
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yes this concept is used widely in many structures but you must use epoxy material to bond the new concrete to the old one and also must roughten the surface of the old concrete before poring new concrete
i agree with dawn836 regarding "reuseing" the rebar, which actually is just leaving the existing bar long enough to lap (development length) into the new section of concrete.  however, the comment that you must use an epoxy bonding agent is not necessarily so.  this connection was made for many years prior to the advent of epoxy bonding agents by wetting the existing concrete, brooming down a sand/cement grout and then pouring the new concrete.
epoxies come in handy for lots of applications and patching jobs, however, they have their limitations too.  for one thing, their coeff. of expansion is very different than that of concrete, so in areas of large tempeture ranges, you must be careful how you use them.