self compacting concrete presentation

1. SELF
COMPACTION
CONCRETE
CREATED BY – PRAMOD G K
4MN17V414

2. CONTENTS
1. INTRODUCTION
2. MATERIALS USED
3. PROPERTIES
4. TEST
5. TYPICAL MIX
6. APPLICATION
7. CONCLUSION

3. INTRODUCTION
 Self-Compacting Concrete or Self-Consolidating Concrete, SCC, is
defined as a Concrete that is able to flow under its own weight and
completely fill the formwork, even in the presence of dense
reinforcement, without the need of any vibration, whilst maintaining
homogeneity.
 Self Compacting Concrete was first developed in Japan in the year
1980.

4. MATERIALS USED FOR SCC
CEMENT : OPC of 43 or 53 grade can be used
AGGREGATES : *Aggregates of size limited to 20mm.
*Congested Reinforcement:10 to 12mm.
*Well graded cubical or rounded aggregates.
*FA can be either natural or manufactured and of
uniform grade
*Particle sizes <0.125mm are considered as fines.
WATER : It must be of the same quality used for that of RC or
Pre stressed concrete.

5. CHEMICAL ADMIXTURE:
*The new generation super plasticizers termed as poly
carboxylate ethers is particularly used.
*VMA : For stability.
*Air Entraining Agents : To improve Freeze-Thaw resistance.
*Retarders : To control setting time.
MINERAL ADMIXTURE:
*GGBS : To improve Rheological Properties.
*Fly ash : To improve the quality and durability.
*Silica Fumes : To improve Mechanical Properties.
*Stone Powder : To increase the powder content.

6. PROPERTIES IN FRESH STATE
 FILLING ABILITY (excellent deformability) :
Flows easily at suitable speed into formwork.
PASSING ABILITY (ability to pass reinforcement without blocking) :
Passes through reinforcements without blocking.
HIGH RESISTANCE TO SEGGREGATION :
The distribution of aggregate particles remains homogeneous in
both vertical and horizontal directions.
 Static segregation due to gravity, vertical direction.
 Dynamic segregation due to flow, horizontal direction.

7. PROPERTIES IN HARDENED STATE
COMPRESSIVE STRENGTH :
Age of 28 days 40 to 80 Mpa.
Age of 91 days 55 to 100 Mpa.
 SPLITTING TENSILE STRENGTH :
2.4 to 4.8
STATIC MODULUS OF ELASTICITY :
30 to 36 Gpa.
BOND RESISTANCE

8. TEST ON SCC
FILLING ABILITY TEST
PASSSING ABILITY
TEST
SEGREGATION
RESISTANCE TEST
Slump Flow Test J-Ring Test V-funnel At T5minutes
T50cm Slump Flow L-Box Test
GTM Screen
stability Test
V-Funnel Test U-Box Test
Orimet Fill-Box Test

9. 1. SLUMP FLOW TEST

10. PROCEDURE
A normal slump cone and a flat square plate is taken . Some concentric
circles are drawn on square plate . A firm circle of 500 mm dia is drawn.
The slump cone is filled with about 6litre of concrete and is raised
vertically and allow the concrete to flow free in horizontal direction.
Measure the final dia of concrete in 2 perpendicular directions and note
the average of two diameters.
ACCEPTABILITY :
The higher the flow rate , the grater is the ability to fill
form work.
A value of at least 650 mm is required for scc and
maximum of 850 mm is allowed.

11. 2. V FUNNEL TEST

12. PROCEDURE
V-funnel test is used to find filling ability of aggregates of maximum
size of 20 mm.
The equipment consists of a v-shaped funnel.
The door present below the v-funnel is closed and about 12 liter of
concrete is poured inside.
Open the door within 10 seconds and record the time taken for concrete
to flow down.
The whole test is to performed within 5 minutes.
ACCETABILITY :
For v-funnel test the flow time should be b/w
8to12min.

13. 3. J RING TEST

14. PROCEDURE
The equipment consists of a rectangular section and a ring of reinforced bars
with holes.
A slump cone is taken and is filled with 6 liters of concrete.
Raise the cone vertically and allow the concrete to flow through the j-ring.
Measure the final diameter in 2 perpendicular directions and take the average
value.
Also measure the difference in height between the concrete just inside J-ring
bars and just outside J-ring bars.
Calculate the average of difference in height at 4 locations.
ACCEPTABILITY: The acceptable difference in height between inside and
out side should be 0 to 10 mm.

15. 4. L BOX TEST

16. PROCEDURE
About 14 liters of concrete is taken and fill the vertical section of L-box.
Lift the gate and allow the concrete to flow out into the horizontal
section.
Start the stop watch and note down the time taken to reach 200 and
400mm marks.
When the concrete stop flowing the heights H1 and H2 are measured.
Calculate blocking ratio H2/H1.
The test is to be performed within 5 min.
ACCEPTABILITY :
 If the concrete flows like water then H2/H1=1
 The minimum acceptable value is 0.8.

17. TYPICAL MIX
CA <50%
WATER:POWDER
0.8 to 1.0
TOTAL PASTE 400 to 600 kg/m^3
SAND CONTENT >40% of mortar
SAND <50% of paste volume
SAND >50% by weight of total aggregates
WATER <200 liters.
>40% of the volume of the mix

18. SCC MIX DESIGN PRINCIPLES
SCC SHOULD HAVE :
 Low coarse aggregate content.
 Increased paste content.
 Low water powder ratio.
 Increased super plasticizer dosage.
 Viscosity modifying agents.

19. APPLICATION

20. ON HEAVILY REINFORCED STRUCTURE

21. LNG TANKS

22. METRO CONSTRUCTION

23. BURJ KHALIFA

24. JAPAN AKASHI KAIKYO BRIDGE

25. CONCLUSION
Self Compacting Concrete (SCC) technology can save time, cost,
enhance quality, durability and Moreover it is a green concept.
Since the concrete is capable of self-consolidating and reaching the
difficult areas in moulds, manual variables interms of placing and
compacting concrete is nil. This factor ultimately yields defect less,
better-quality concrete structures.
Cast-in-place concrete construction in tight space and congested
reinforcement, such as, drilled shafts, columns and earth retaining
systems, can be accelerated by using SCC.