huangyhg

support for footing reinforcement
at a recent visit to a job site, i was observing the reinforcement for a cmu cantilevered retaining wall with a concrete footing. the hooked dowels extending out of the footing were supported by tying an additional vertical rebar to each dowel, and embedding it in the earth.
this seems like a very poor practice in that it provides a path for water to enter the footing and corrode the reinforcement.
should i make the contractor remove the embedded rebar and support the dowels with chairs or small cmu blocks? anyone know of any articles addressing this concern?
thanks
ice
am i correct in saying that the footings haven't been poured yet? then you noticed the dowels as you mentioned? i am not sure how much of a path this will create for water to enter the footing given that the footing is no more likely to crack at service loads with this sort of rebar support. as a general cost consideration i have to think it is more expensive to be throwing rebar into the ground to support rebar, rather than using chairs or small block as you mentioned above.
we categorically reject any rebar supported this way that we find during our inspections. it is contrary to crsi placing reinforcing standards and is downright stupid.
you should reject it immediately and have the contractor do it right.
i would also say reject. he should be using rebar chairs or supporting the bars from above.
i saw bars shown this way on the design for a school i reviewed recently. i didn't like it but was left wondering if there is an official position by crsi which prohibits this practice.
technically it violates code.
in reality, unless the soil is very aggressively corrosive, by the time the entire length of rebar corrodes so that the rest of the steel can begin to corrode and cause a problem, the structure has probably lived its useful life anyway. i'd make them fix it since you saw it and it violates code and is another magnet you're wearing for liability.
thanks for the replies.
ucfse- where in the code is this prohibited?
contractors complained that chairs "sink" into base (compacted soils or aggregate), so i specified solid concrete bricks for bar supports. the dimensions (i think 2.5-inch thick and 3.5-inch wide) of concrete bricks do not provide 3-inch clear cover. inspector needs to check clearances prior to concrete placement.
good luck
this situation has occurred for me in the past. i made contractors remove such bar supports and replace with either chairs or precast concrete bricks. or, support the bars from above in some manner.
aci 318-05, 7.7.1
it violates minimum clear cover provisions.

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