Concrete Unit Weight & Density Test Equipment

Select the Measure and the Scale

Standard test methods for density (unit weight) and yield of fresh concrete use a calibrated measure of known volume. Compare the steel unit weight measure, 1/2 cu ft and the 1/3 cu ft steel measure with the aluminum options, including the 1 cubic foot aluminum unit weight bucket, against the nominal maximum aggregate size and procedure volume your method specifies.

Pair the measure with a scale of suitable capacity and readability, such as the Digital Field Scale, 220lb. Verify the measure volume and scale calibration status before testing; an unverified measure makes every density figure that follows unreliable.

Complete the Setup with Rod, Plate and Technique

Consolidation and strike-off determine whether the sample fills the measure correctly. Use a tamping rod such as the Concrete Tamping Rod, 12 x 3/8in where the procedure calls for rodding, and level the surface with a strike-off plate like the 10 x 10in aluminum strike-off plate or the 12 x 12in plate.

Follow the specified consolidation method, number of layers and strike-off technique rather than improvising. Overfilling, under-filling or a careless strike-off changes the sample volume and distorts the calculated unit weight, so confirm the technique against the governing method before each test.

Interpret Unit Weight, Yield and Air Content

Density testing typically reports unit weight, yield and estimated air content from the same sample. Unit weight is the sample weight divided by the measure volume; yield compares the actual volume of concrete produced with the intended volume, and the air estimate compares measured density with the theoretical density calculated from mixture proportions.

Record each figure with the batch information your quality program requires, and treat a low unit-weight reading as a prompt to check air content and mixture proportions. For air measurements, compare concrete air meters separately, and use the fresh concrete testing equipment category to plan the complete field setup.