ACI 301 Rolling Average
ACI 301 Rolling Average
(OP)
Does anyone know if the rolling average as described in ACI 301 sections 1.6.6 and 1.6.7 apply when the same mix design was being produced at two different concrete plants?
We molded 7 sets of cylinders for a large elevated deck pour, and the 5th set of cylinders we molded came from a truck that was from one plant, and all of the other sets of cylinders we molded came from another plant.
The one set that we made from a different plant was the only one that did not meet the specified f'c.
We molded 7 sets of cylinders for a large elevated deck pour, and the 5th set of cylinders we molded came from a truck that was from one plant, and all of the other sets of cylinders we molded came from another plant.
The one set that we made from a different plant was the only one that did not meet the specified f'c.





RE: ACI 301 Rolling Average
In computing the moving average, use only those results from a single batch plant.
RE: ACI 301 Rolling Average
RE: ACI 301 Rolling Average
Were all handled and cured in a similar manner.
What is your climate? Different plants can have different aggregate temperatures depending on the storage method and rate of use if you are in a cold climate. This will have an effect of 7 day or quicker breaks.
do you have access to print-outs of the individual batches - most good plant systems can retreive the information. This can be helpful to determine if the same materials were used.
RE: ACI 301 Rolling Average
What if plant A breaks down during a pour and a switch is made to plant B?
RE: ACI 301 Rolling Average
In evaluating a moving average, it is appropriate to use the data from each plant, but separately. Do not mix data from one plant to another for a moving average computation.
RE: ACI 301 Rolling Average
You may wish to monitor trends, one plant vs. another, but the mix is considered the same mix if the mix ID and ingredients are the same.
RE: ACI 301 Rolling Average
Even though the mix "recipe" might be the same and being produced by two different plants of the same company, there are still variables between the plants. They have different scales, their storage/conveyances are often different, they use water from two different sources, and variations in production rate might mean that material sources/timing may change enough to affect the mix consistency.
RE: ACI 301 Rolling Average