Concrete Yield Verification Calculator
Check the actual volume produced by a concrete batch using its total mass and measured fresh density, then compare that yield with the expected batch yield to expose shortages, overruns or production drift.
Verify the batch
Actual concrete yield
The yield formula
ASTM C138 defines yield as the volume of concrete produced from known quantities of component materials. In the simple verification model, actual volume is total batch mass divided by measured fresh density.
The units must be compatible. For example, kilograms divided by kilograms per cubic metre produces cubic metres.
Worked example
A batch with 24,000 kg total mass and 2,400 kg/m³ fresh density produces:
If the expected yield is also 10.00 m³, the arithmetic variance is zero.
Why yield matters in production
Concrete can be technically within its ingredient proportions and still produce a different volume than expected. Yield verification can reveal a batching or density problem that might otherwise appear as unexplained shortage or surplus at the placement site.
Yield is also related to the absolute-volume concept in concrete mixture proportioning. Actual production should be checked against the approved mix and measured fresh properties.
Technical context: ASTM C138/C138M.
Yield variance is a diagnostic signal
A negative yield variance means the calculated production volume is below expectation. A positive variance means it is above expectation. Neither number identifies the cause by itself.
Possible contributors include inaccurate ingredient batching, density changes, moisture corrections, air-content changes, recording errors or differences between theoretical and actual batch quantities.
Common errors
Mixing units: kg and lb cannot be divided by the wrong density unit.
Using hardened concrete density: the calculation is for fresh concrete.
Comparing unlike batch sizes: expected yield should correspond to the entered batch.
Assuming variance identifies the root cause: further investigation is needed.
Limitations
This calculator checks the mass-density relationship. It does not measure fresh density, validate batching accuracy or determine the reason for a yield discrepancy.
Frequently Asked Questions
What is concrete yield?
The actual volume produced by a known batch of concrete.
How do you calculate yield?
Divide total fresh-concrete batch mass by measured fresh-concrete density.
Can yield be higher than expected?
Yes. The calculated variance can be positive.
Does yield variance prove a mix is wrong?
No. It indicates a difference that needs investigation.
Which ASTM standard covers yield?
ASTM C138/C138M covers fresh-concrete density, yield and gravimetric air content.