IS 10079 : 1982Specification for cylindrical metal measures for use in tests of aggregates and concrete

IS 10079:1982 is the specification for cylindrical metal measures used in tests of aggregates and concrete — the calibrated rigid containers of known volume used to determine bulk density (unit weight) and voids of aggregate and the unit weight / yield of fresh concrete. It is an apparatus spec, but it underpins two everyday conversions: turning a *volume batch* into a *mass batch*, and back-calculating actual yield.

It sits with the test methods that use it:

• IS 2386 Part 3 — bulk density & voids of aggregate (uses these measures) · IS 1199 Part 2 — unit weight / yield of fresh concrete
• IS 10262 — mix design (bulk density converts the volumetric proportions) · IS 383 — aggregate

Bulk density = mass of compacted/loose aggregate ÷ measure volume; concrete unit weight = mass ÷ measure volume — so the *volume* must be exact and stable. IS 10079 fixes:

• A set of capacities (small for fine aggregate / fresh-concrete checks, larger for coarse aggregate — e.g. 3 L, 15 L, 30 L class sizes), cylindrical, rigid, watertight, with a machined top rim
• Wall thickness and rigidity so the measure doesn't bulge when rodded/vibrated (a flexing measure has no fixed volume)
• Calibration by water (mass of water filling the measure at a known temperature) — the volume is *measured*, not nominal

The engineering point: if the measure's volume is wrong or it deforms, every bulk-density-derived figure is wrong — the volume-to-mass batching conversion, the voids ratio, and the concrete yield check that tells you whether you got the cubic metres you paid for.

Scenario: determine 20 mm aggregate rodded bulk density, then check concrete yield.

Step 1 — calibrate: weigh the empty measure; fill with water, weigh; volume = water mass / density → the *true* volume (don't trust the nameplate).

Step 2 — bulk density: fill the measure with aggregate in three layers, 25 rod strokes per layer (IS 2386 Part 3), strike level, weigh. Bulk density = (gross − tare) / true volume → e.g. ~1600 kg/m³.

Step 3 — voids: voids % = [1 − bulk density / (specific gravity × 1000)] × 100.

Step 4 — concrete yield: fill a measure with fresh concrete (compacted per IS 1199 Part 2), weigh → unit weight; yield = total batch mass / unit weight. Compare to design volume — a short yield means the mix isn't delivering the cubic metres assumed in costing and cover.

Every number here is only as good as the calibrated measure volume.

1. Using the nameplate volume. Always re-calibrate by water mass — manufacturing tolerance and dents move the real volume.

2. A thin, deforming measure. A measure that bulges under rodding/vibration has no fixed volume; rigidity is part of the spec for a reason.

3. Wrong measure size for the aggregate. Too small a measure for 40 mm aggregate gives a non-representative, scatter-prone bulk density.

4. Loose vs rodded confusion. Loose and rodded (compacted) bulk density are different numbers — report which, and use the one the calculation expects.

5. Ignoring the yield check. Skipping the concrete unit-weight/yield test hides over- or under-yielding mixes — a quiet cost and cover problem on every pour.

• IS 2386 Part 3 — bulk density, voids & bulking of aggregate (primary user of these measures)
• IS 1199 Part 2 — unit weight & yield of fresh concrete
• IS 10262 — mix design (bulk density converts volumetric proportions)
• IS 383 — aggregate specification · IS 456 — concrete

IS 10079 is a quiet apparatus standard, but the calibrated measure sits behind two things engineers actually argue about: volume-batched site mixes and concrete yield. Volume batching only works if bulk density is right; the 'we're short of concrete / cover is thin' complaint is a yield problem the unit-weight test would have caught early. The recurring error is trusting the stamped capacity and using a dented or flimsy measure — calibrate by water mass, keep it rigid, pick the size to suit the aggregate, and always run the yield check. It's a small instrument that quietly governs whether the cubic metres designed are the cubic metres in the structure.