2. Mix Proportioning Principles as per IS 10262:2019
a) Lower coarse aggregate content,
b) Increased paste content,
c) Low water/powder ratio
NOTE — Powder refers to materials of particle size smaller than 0.125 mm.
It includes this size fraction from cement, mineral admixtures and aggregate.
Water/powder ratio shall be 0.85 to 1.10 by volume.
d) Increased superplasticiser, and
e) Use of a viscosity modifying admixture at times.
3. Typical Range of Mix Constituents as per IS 10262:2019
a) Powder Content (< 0.125 mm) in the range of 400 kg/m3 to 600 kg/m3, inclusive of
suitable quantities of fine aggregate and mineral admixtures like fly ash in suitable
proportions, may be used for flowability while ensuring compliance with
engineering properties particularly shrinkage.
Fine aggregate content, typically, 48 to 60% by mass of the total aggregate, balances
the volume of the other constituents.
b) Water content between 150 to 210 kg/m3.
4. Classification of SCC based on Fresh Prop. test Results
Sl.
No.
Class/
Type
Desired Range
of Slump flow
Applications
1 SF1 550 - 650 mm
Unreinforced or
Lightly reinforced concrete
2 SF2 660 - 750 mm
Normal applications
(for example, walls, columns)
3 SF3 760 - 850 mm
Vertical applications in
heavily reinforced structures,
structures with complex shapes,
or for filling under formwork
a) Classification based on Slump Flow c) Classification based on V-Funnel
Sl.
No.
Class/
Type
Desired
Range of
V-Funnel
Flow
Time
Applications
1
V1
(Less
Viscous/
Better
Flow)
< 8 sec
Good filling ability even
with congested
reinforcement. It is
capable of self-leveling
and has the best surface
finish
2
V2
(Higher
Viscosity/
Less
Flow)
8 – 25 sec
Improved segregation
resistance. May Cause
negative effects on
surface finish and is
sensitive to stoppages
or delays between
successive lifts
Sl.
No.
Class/
Type
Desired Range
of Segregation
ratio
Applications
1
SR1
(More
Segregation)
15-20%
Thin slabs and for vertical
applications with flow distance of
less than 5 m and a confinement
gap greater than 80mm
2
SR2
(Less
Segregation)
< 15%
Vertical applications if the flow
distance is more than 5 m with a
confinement gap greater than 80mm
b) Classification based on Segregation Resistance
5. Mix Design Steps as per IS 10262:2019
Step 1: Target Strength for Mix Proportioning
Step 2: Selection of approximate Air Content based on maximum aggregate size
Step 3: Selection of Water-Cementitious Materials Ratio (w/cm)
Step 4: Selection of Water Content and Cement/Fly Ash (or other SCM) content.
Step 5: Selection of admixture content
Step 6: Selection of powder content and computation of fine aggregate content
Step 7: Computation of Coarse aggregate content
Step 8: Calculation of volume of powder content & Check for water/powder ratio by volume
Step 9: Mix proportions for trial 1
