- Thread starter caprinut
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Nomad
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- North Devon (for how long?)
What are you planning to use it for / on / in ?
I used some last week that had been sat in the garden for many years, it was too weakened to use safely in construction but was fine to use as locating pegs while I was building a platform out of logs.
I used some last week that had been sat in the garden for many years, it was too weakened to use safely in construction but was fine to use as locating pegs while I was building a platform out of logs.
BrokenBiker
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Depends on application...for use as rebar in structural concrete, then it's probably too far gone already..to weld up as hooks or brackets then it will probably be fine...
frank horton
V twins are great but 4"s rule.........
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if u can chip rusty bits off "flakes" ...get some more for structural jobs, although for things like garden gate posts etc it'll be OK....
I know it's nuts but I now paint mine when I buy for stock....
I make garden ornaments with it.
I know it's nuts but I now paint mine when I buy for stock....
I make garden ornaments with it.
Agroshield
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Depending on what you are using it for, you could crop to length, give it a vinegar jacuzzi (length of rainwater gutter or 4" soil pipe) and once all the corrosion is removed, use it nearly as normal. Make some reasonable judgement call on the amount of material lost, but putting in one extra bar or reducing the centres by 25mm might be OK.
Rebar works by being bonded to the steel so a friable surface will be massively more harm than a slightly reduced cross sectional area.
Rebar works by being bonded to the steel so a friable surface will be massively more harm than a slightly reduced cross sectional area.
brightspark
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rusted rebar blows the concrete
Concrete cancer I believe it's called.
Agroshield
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That is not quite correct.
Rebar that is enabled to rust while embedded in concrete will expand and spall the concrete. For that to happen, it needs oxygen and moisture.
Encapsulating an already rusty piece of steel into concrete removes the oxygen and moisture supply and it will not change condition.
Rules and regs for how deep concrete cover needs to be for rust jacking prevention. A decent survey of industrial buildings will include a depth scan - not too good if too shallow. AI says:
The minimum thickness of concrete over rebar, or concrete cover, varies based on the application and environmental conditions, but common minimums include 25 mm for internal, protected conditions and 50 mm for external applications. For concrete in contact with the ground, the minimum cover is often 75 mm, while concrete poured against a vapor barrier or blinding concrete typically requires 40 mm. The thickness must be sufficient to protect the rebar from corrosion caused by moisture and carbonation.
The minimum thickness of concrete over rebar, or concrete cover, varies based on the application and environmental conditions, but common minimums include 25 mm for internal, protected conditions and 50 mm for external applications. For concrete in contact with the ground, the minimum cover is often 75 mm, while concrete poured against a vapor barrier or blinding concrete typically requires 40 mm. The thickness must be sufficient to protect the rebar from corrosion caused by moisture and carbonation.
