Self-compacting concrete (SCC) is a highly flowable concrete that can spread into place and fill formwork without any mechanical consolidation. SCC was developed in Japan in the 1980s to ease construction challenges. SCC consists of the same materials as regular concrete but with optimized proportions and use of chemical and mineral admixtures to improve flowability and prevent segregation. Tests are conducted to evaluate the filling ability, passing ability and resistance to segregation of SCC. While SCC provides benefits like faster construction and improved quality, further research is still needed to fully understand its properties. SCC has been used successfully in large projects in Japan and India.

1. SELF COMPACTING
CONCRETE
Prepared by-
Meet Shah
IndusInstituteofTechnology& Engineering

2. • Most revolutionary development in concrete
construction for several decades.
• SCC is modern innovation- does not require
vibration for placement and compaction.
• Flowing consistency, High
Performance, Uniform quality.
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3. Contents
 Introduction
 History
 Why Self Compacting Concrete?
 Material Selection
 The Requirements for SCC & Production
 Test Methods for Compactibility
 Complexities involved in SCC
 Application
 Conclusion
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4. Introduction
The guiding principle for this type of concrete is
that the sedimentation velocity of a particle is
inversely proportional to the viscosity of the floating
medium in which the particle exists.
A special type of concrete of flowing consistency
to obtain high performance, better and more
reliable and uniform quality.
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5. History of SCC
1983 Concrete crisis in Japan, and concern for durability of concrete
structures
1986 Basic concept by Prof. H. Okamura of Tokyo University
1988 Prototype for field experiments and implementations
1989 Open experiment
1991 Jt. Research project with construction companies
1993 “High Performance Concrete” established
1994 International Workshop on HPC in Bangkok
1997 Technical Committee in RILEM
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6. Difficult to use mechanical compaction for
Underwater concreting
Cast in-situ pile foundation
Columns with congested reinforcement
Why Self Compacting Concrete
?
The existing concrete has faced criticism for its lower
strength and difficult to obtain consistent quality.
Requirement of skilled worker for compaction in
conventional concrete
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7. Benefits of SCC
 Faster Construction
 Reduction in site manpower
 Better surface finish
 Easier placing
 Improved durability
 Greater freedom in design
 Thinner concrete sections
 Reduced noise level
 Safer working environment
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8. Materials Selection for SCC…
Cement
Aggregates
Chemical Admixtures
Mineral Admixtures
Mixing Water
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9. Material Selection
With regard to its composition, SCC consists of the
same component as conventionally vibrated concrete,
which are:
CEMENT
Ordinary Portland Cement of 43 or 53
grade can be used.
Coarse Aggregates
Crushed granite aggregate with nominal size
<12.5 mm and specific gravity 2.56.
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10. Continued…
Chemical Admixtures
Superplasticizers provide necessary workability.
Viscosity Modifying Agents (VMA), provide
stability.
Air entraining agents improve freeze-thaw
resistance.
Fine Aggregates
Zone-III sand passing through 4.75 mm sieve of
specific gravity 2.56.
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11. Continued…
Mineral Admixtures
Fly Ash : Improve the quality and durability.
Ground Granulated Blast Furnace Slag(GGBFS)
Silica fume : Improve mechanical properties of
SCC.
Stone powder : Finely crushed lime stone,
dolomite or granite.
Fibres : Enhance the properties of SCC
Mixing Water
Ordinary potable water of pH ranging
from 7 to 8.5.
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12. The Requirements for Self-
Compacting Concrete
 Filling ability
 Passing ability
 Segregation resistance
SCC should have
 Low coarse aggregate content
 Increased paste content
 Low water powder ratio
 Increased super plasticizer dosage
 Viscosity modifying agents
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13. Reduction of
water to
binder ratio
Limitation of
coarse
aggregate
content
Addition of
mineral
admixture
High segregation
resistance of mortar &
concrete
High deformability
of mortar & concrete
Self Compactibility
Flow Chart for achieving Self
Compactibility…
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14. » Increasing the powder content.
» Increasing the powder content and using VMA.
» Adding viscosity modifying admixture.
 Powder Type,
 Viscosity Modifying Agents Type,
 Combined Type,
Self-Compacting Concrete can be
distinguished into:
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15. Test Methods for compactibility
• Filling Ability
 Slump flow test, T50 cm slump flow test, V-Funnel test
• Passing ability
 J-ring test, U-box, L-box
• Segregation potential
 Settlement column Test, Sieve stability test, Penetration
test
Although many test methods have been developed for
SCC but none has been standardised and the tests are
not perfected.
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16. 1. Slump Flow Test
Property: Filling, Ability and Segregation
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17. 2. L-Box Test
Property: Passing
ability, blocking
effect

18. 3. J-Ring Test
Property: Flowing ability, passing ability
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19. Complexities involved in SCC
 Higher paste volume results in greater
shrinkage and creep.
 Higher strength achievement leads to
reduced workability to unacceptable level.
 Lateral Formwork pressure.
 Limit of flow distance of the concrete.
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20. Application
 Two anchorages of Akashi-Kaikyo (Straits) Bridge,
Japan. The volume of the cast concrete in the two
anchorages amounted to 290,000 m3
 The highest use of SCC in India was done at Delhi
metro project. About 10000 m3 of SCC has been
Used.
 At Kaiga nuclear power plant, SCC of Characteristic
strength 30 MPa was used.
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22. Conclusion
 We can reduce the in-place cost and maker a safer
working environment for the workers.
 SCC can be effectively placed in most congested areas
and also where normal methods of vibration are not
possible.
 Further research are required to interpret influence on
the hardened properties of SCC more precisely.
 The cost of SCC is 10-15 % higher than the
conventional concrete.
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23. OUR ROLE
 Maximum Application of self compacting concrete.
 Learning and guiding workers to implement the self
compacting concrete.
 To identify test methods for SCC to improve its
workability.
 Forming IS codes for the self-compacting concrete.
As an Engineer:
As a Researcher:
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