Which workability test should I use?

Slump for plastic medium/high-workability concrete; compacting factor for stiff/dry mixes (slump insensitive); flow/Vebe for special very-stiff mixes. Pick the test sensitive in your workability range and trend it.

Does IS 1199 cover self-compacting concrete?

No — SCC uses its own fresh-test suite (slump-flow, L-box/J-ring, sieve segregation; IS 15658). The IS 1199 slump is not a valid SCC control.

IS 1199:2018 — Fresh Concrete — Methods of Sampling & Testing (Pa…

IS 1199:2018 — Clause G

Choosing the Right Workability Test & Control Discipline

IS 1199 provides several workability tests because no single test suits all concretes: slump (Part 2) for medium/high-workability plastic concrete, compacting factor (Part 3) for stiff/dry mixes where slump is insensitive, and flow/Vebe-type methods for special or very stiff mixes. The control discipline is to pick the test that is sensitive in the mix's workability range and trend that metric batch-to-batch.

Key Requirements

•Plastic / medium-high workability → slump (Part 2)
•Stiff / dry / low-slump → compacting factor (Part 3)
•Very stiff / special mixes → flow / Vebe-type per the relevant part
•Trend the chosen metric batch-to-batch as the early-warning control (water / aggregate-moisture drift)
•SCC is NOT covered by these — it uses the SCC fresh tests (slump-flow/L-box/J-ring, IS 15658)

Practical Notes

✓The error is using slump for everything — for stiff/PQC mixes slump is flat and meaningless; use the compacting factor and trend it.

✓Self-compacting concrete needs the SCC fresh-test suite (IS 15658), not the IS 1199 slump — don't conflate them.

Common Mistakes

⚠Slump used for stiff/dry mixes where it is insensitive.

⚠No batch-to-batch trending of the workability metric (loses the early-warning value).

⚠Applying IS 1199 slump to SCC (use the SCC fresh tests instead).

Frequently Asked Questions

Related Resources

Cl. slump Cl. compacting.factor Cl. density.air Cl. sampling

View all 5 clauses of IS 1199:2018 →