Concrete Mix Design and Placement Responsibility
Concrete Mix Design and Placement Responsibility
(OP)
Who is ultimately responsibile for the durability and strength of concrete? Just the material itself, not the design of reinforced beams slabs etc. Typically, a concrete supplier puts together a mix design and submits it to the engineer per ACI procedures for approval. I have a contractor sending me RFI's asking if adding retarder to the mix and placing a vapor barrier below is acceptable to extend workability for a set of stairs on grade.
I feel it's the concrete suppliers responsibility to advise the contractor on something like this. All Im concerned about is achieving the final strength and durability.
How do you typically respond?
I feel it's the concrete suppliers responsibility to advise the contractor on something like this. All Im concerned about is achieving the final strength and durability.
How do you typically respond?






RE: Concrete Mix Design and Placement Responsibility
RE: Concrete Mix Design and Placement Responsibility
Just trying to figure out who's really responsible for what in the event there's major cracking. I dont want anyone to turn around and say it's the engineer's fault because he approved it.
RE: Concrete Mix Design and Placement Responsibility
Dik
RE: Concrete Mix Design and Placement Responsibility
The contractor is requesting information from you as a variance to the project - the specs may not call for a retarder. If you wish, ask the contractor to provide details as to the revision of the mix design, confirmation that the revised mix design will meet the project specifications and you may give a "no objection" or not. If the retarder is a variance to the design, you don't have to accept it. Similarly, the vapor barrier is your call as the Design Engineer. If you are not the design engineer, then the design engineer needs to be queried.