What is the main test for SCC workability?

The slump-flow test, which measures the horizontal spread of the concrete. The target diameter is typically between 650 mm and 800 mm (Table 1).

How is the ability of SCC to flow through reinforcement checked?

Using the J-ring test (measures the difference in height inside and outside the ring) or the L-box test (measures the blocking ratio). (Clause 6.3 & 6.4).

What is the acceptable flow time from a V-funnel?

A V-funnel time (Tv) of 6 to 12 seconds is generally considered acceptable, indicating good flowability and viscosity. (Table 1).

What kind of admixtures are used in SCC?

A new generation of polycarboxylate ether (PCE) based superplasticizers (or high-range water-reducers) are essential for achieving high flow without segregation. (Clause 4.3).

IS 15830

: 2008

Self-compacting concrete - Guidelines

CurrentSpecializedGuidelinesBIMMaterials Science · Admixtures and Chemical Products for Concrete

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This standard provides guidelines for producing and using self-compacting concrete (SCC). It details the required properties of fresh SCC, such as filling ability, passing ability, and segregation resistance, and prescribes the specific test methods (like slump-flow, J-ring, and V-funnel) to verify them. The code also offers guidance on material selection and mix proportioning.

Provides guidelines for the production and use of self-compacting concrete, heavily reliant on superplasticizers.

Quick Reference Values

Slump-flow diameter (SF1 Class)550-650 mm

Slump-flow diameter (SF2 Class)660-750 mm

Slump-flow diameter (SF3 Class)760-850 mm

T500 time for slump flow2-5 s

V-funnel flow time (Tv)6-12 s

J-ring test step height≤ 10 mm

L-box test blocking ratio (H2/H1)0.8 - 1.0

Sieve segregation resistance≤ 20 % (often targeted ≤ 15%)

Practical Notes

SCC performance is highly sensitive to water content and the quantity of fines; small variations can drastically alter flow properties. Strict quality control of materials and batching is critical.

Formwork must be exceptionally well-sealed and braced to prevent leakage and withstand the higher hydrostatic pressure exerted by the fluid SCC.

During the slump-flow test, observe the perimeter of the spread for a 'halo' of bleed water or mortar, which indicates potential instability and segregation issues in the mix.