Self-compacting concrete (SCC) is a highly flowable concrete that can spread into place and fill formwork without mechanical vibration. SCC has a slump flow ranging from 1 to 32 inches depending on project requirements. It is used to allow faster placement without vibration, improve surface finish, ease placement in restricted areas, and improve consolidation around reinforcement. SCC achieves its flowability through superplasticizers and stability through a higher paste volume, less coarse aggregates, and a higher sand-to-coarse aggregate ratio than conventional concrete. Proper testing ensures SCC does not segregate or bleed once placed.

1. SELF COMPACTING CONCRETE
BY:
B.NIKHIL KUMAR

2. WHAT IS SCC?
• SCC stands for self compacting concrete or self
consolidating concrete.
• It is highly flowable, non-segregating concrete
that can spread into place , fill formwork and
encapsulate the reinforcement without any
mechanical consolidation.
• The spread (slump flow) of SCC typically
ranges from 1 to 32 inches depending on the
requirements for the project.

3. • Modern application of self-compacting
concrete is focussed on high performance,
better and more reliable and uniform quality.

4. WHY IS SCC USED?
• Can be placed at a faster rate with no
mechanical vibration and less
screeding,resulting in savings in placement
costs,
• Improved and more uniform architectural
surface finish with little to no remedial surface
work.
• Ease of filling in restricted sections and hard to
reach areas.

5. • Improved consolidation around reinforcement
and bond with reinforcement.
• Improved pumpability.
• Improved uniformity.
• Labour savings.
• Shorter construction periods and resulting
cost savings.
• Service the project more efficiently.
• Reduction of vibrator noice.

6. MATERIALS FOR SCC
• CEMENT: OPC of 43 or 53 grade
• AGGREGATES: The maximum size of
aggregates is generally limited to 20 mm.
• MIXING WATER: It is estimated on same line
as reinforced concrete.
• CHEMICAL ADMIXTURES: Superplaseizers are
an essential component of SCC to provide
necessary workability.

7. • Examples of SCC mixes are
A)Powder type
B)VMA type
C)Combined type
• The mix design is focussed on the ability to
flow under its own weight without vibration.
• The workability of SCC is higher than “very
high” degree of workability mentioned in
IS 456:2000.

8. HOW IS SCC ACHIEVED?
• Two important properties specific to SCC in its
plastic state are its FLOWABILITY and
STABILITY.
• The high flowability of SCC is generally
attained by using high range water reducing
admixtures(HRWR).
• The stability to segregation of the plastic
concrete mixture is attained by increasing the
total quantity of fines in the concrete.

9. • SCC mixtures have typically higher paste
volume , less coarse aggregates and higher
sand coarse aggregates ratio than typical
concrete mixtures.
• If the SCC mixture is designed to have a higher
paste content or fines compared to
conventional concrete , an increase in
shrinkage may occur.
• Once the concrete is in place it should not
display segregation or bleeding/settlement.

10. HOW TO TEST SCC?
• Different types of tests are:
• A)SLUMP FLOW TEST
• B)J-RING TEST
• C)V -FUNNEL TEST
• D)L BOX TEST
• E)U-BOX TEST
• F)FILL BOX TEST
• G)ORIMENT TEST

11. THANK YOU