This study investigated concrete mixes made with partial replacements of cement by ground granulated blast furnace slag (GGBFS) and silica fume. Tests were conducted to determine the compressive, split tensile, and flexural strengths of mixes with 20-50% GGBFS and 5-10% silica fume. The mixes were designed to M30 grade and tested at 7, 14, and 28 days. Results showed that mixes with 30-40% GGBFS and 7.5% silica fume achieved the highest strengths. This study concluded that using GGBFS and silica fume can produce high strength concrete while reducing the environmental impact of cement production.

1. STUDY ON CONCRETE MADE
WITH
GROUND GRANULATED BLAST FURANCE SLAG
AND SILICA FUME
AS PARTIAL REPLACEMENT OF CEMENT

2. INTRODUCTION
 The Ordinary Portland Cement (OPC) is one of the main ingredient
used for the production of concrete and has no alternative in
the civil construction industry
 Unfortunately, production of cement involves emission of large
amounts of carbon-dioxide gas into the atmosphere
 It is a major contributor for greenhouse effect and the global
warming

3. Introduction – Contd…..
Pozzolanic materials which are going to be used here for making
concrete as partial replacement of cement are,
Ground Granulated Blast Furnace Slag
Silica Fume
 The search for any such material, which can be used as an
alternative or as a supplementary for cement should lead to
o Global sustainable development and
oLowest possible environmental impact

4. Ground Granulated Blast Furnace Slag
• Ground-granulated blast-furnace slag (GGBS or GGBFS) is
obtained by quenching molten iron slag (a by-product of iron and
steel-making) from a blast furnace in water or steam, to produce
a glassy, granular product that is then dried and ground into a fine
powder.

5. EARLIER RESEARCHES on GGBFS
 Liu, Sun and Zhu (1978) found that the use of GGBFS as a
partial Portland cement replacement takes advantage of the energy
invested in the slag making process and
Grinding slag for cement replacement requires only about 25
percent of the energy needed to manufacture Portland cement.
Hog- an and Meusel (1981) Partial replacement of Portland
cement with GGBFS is found to improve the sulfate resistance of
concrete & High resistance to sulfate attack

6. EARLIER RESEARCHES – Contd…
•Roy and Idorn (1982) found a correlation of heat of hydration to
strength potential of various blends of GGBFS and Portland cement
•The heat of hydration is dependent on the Portland cement used and
the activity of the GGBFS.
•GGBFS mortar gains strength more slowly than Portland cement
mortars.

7. OBJECTIVES OF THIS STUDY
1) To investigate different concrete mix with Ground Granulated Blast
Furnace Slag with Silica Fume and determine its
◊ Compressive strength ◊ Split tensile strength ◊ Flexural strength
& comparing the results
2) To determine the water/ binder ratio, so that design mix having
proper workability and strength

8. SCOPE OF STUDY
This study aims,
•To develop concrete with good strength, less porous, less
permeability so that durability will be reached
•To characterize the optimum percentage of Ground Granulated
Blast Furnace Slag with Silica Fume blended cement concrete
•To meet out the strength requirements in compression strength,
split tension strength and flexure strength

9. Procurement of Materials
Testing of Materials
Mix Design
Casting
Concrete Cubes
Concrete beams &
Concrete Cylinders
for M30
As per IS-10262-1982
Testing
Compression
Flexural Strength
Split Tensile
Analyzing &
Comparing the results
Fineness, Fineness Modulus,
Setting time, Specific gravity
Cement, GGBFS,
Silica fume, Super plasticizer,
Coarse & Fine Aggregates
METHODOLOGY:

10. MATERIALS
The compressive strength for high strength concrete was found by
using various properties of following materials
Cement
Ground Granulated Blast Furnace Slag
Silica Fume
Admixture
Fine Aggregate
Coarse Aggregate
Water

11. GROUND GRANULATED BLAST FURNACE SLAG
Ground Granulated Blast furnace slag is a by-product for
manufacture of pig iron and obtained through rapid cooling by
water or quenching molten slag.
The molten slag is produced which is instantaneously tapped
and quenched by water.
This rapid quenching of molten slag facilitates formation of
“Granulated slag”.
Ground Granulated Blast furnace Slag is processed from
Granulated slag.
If slag is properly processed then it develops hydraulic property
and it can effectively be used as a pozzolanic material.

12. GGBFS - Features
White in color
More strength
Makes your projects resistant to chloride attack
Increases the life of the structure more than 50%

13. ADVANTAGES OF GGBFS
Reduce heat of hydration
Refinement of pore structures
Reduce permeability to the external agencies
Increase resistance to chemical attack.

14. Reaction Mechanism of GGBFS
Although GGBFS is a hydraulically latent material, in
presence of lime contributed from cement, a secondary
reaction involving glass (Calcium Alumino Silicates)
components sets in.
As a consequence of this, cementations compounds are
formed.
They are categorized as secondary C-S-H gel

15. SILICA FUME
Silica Fume also referred as micro silica or condensed Silica Fume is
another material that is used as an artificial pozzolanic admixture.
It is a product resulting from reduction of high purity quartz with
coal in an electric arc furnace in the manufacture of silicon or
ferrosilicon alloy.
Chemical Properties :
High silicon dioxide content (90-96%)
Very low carbon content ( 0.5-1.4 %)

16. Physical properties of Silica Fume :
Colour:
varies from white or pale grey to a dark grey
Specific gravity :
it is generally equal to that of amorphous silicon which is about 2.2,
depending upon its chemical composition the specific gravity of silica fume
can be as high as 2.40-2.55.
Specific surface area:
about 20,000 m²/kg approximately 10 times more than ordinary
Portland cement.
Particle size : Mostly fine spheres with a mean diameter of 0.1 micron
which is 100 times smaller than cement particles.
Bulk loose density : 230-300 Kg/m³

17. ADVANTAGES of Silica fume
High strength concrete made with silica fume provides
high abrasion/corrosion resistance.
 It influences the rheological properties of fresh concrete, the
strength, porosity and durability of hardened mass.
 Silica Fume concrete with low water content is highly resistant
to penetration of chloride ions.
 The extreme fineness of Silica Fume allows it to fill or pack
the microscopic voids.
 Silica Fume reduces bleeding segregation of fresh concrete
significantly.
 Highly durable concrete can be obtained by improving the
electrical resistivity of concrete.

18. ADMIXTURES
Cera Hyper plaster XR-W40 is used which is high range water
reducing admixture based on Polycorboxylate allowing long
slump retention than normal super plasticizers, thereby enabling
the production of highly flowable and self-compacting concretes

19. PROPERTIES OF ADMIXTURE
Appearance Liquid
Color Beige ( Pale yellowish)
Chemical Polycarboxylate
Composition Eather
Active Ingredient 40 %
Specific gravity 1.11
Ph 7 - 8
Chloride content nil

20. TESTS ON CEMENT
•Fineness by Sieve Analysis
- The fineness of cement is 3.33% and it should be less
than 10 % (as per IS4031-1996).
- Specific surface – 290 m²/kg > 225 as per IS 12269-1987
•Initial And Final Setting Time
-Initial setting time - 200 minutes >30 minutes
-Final setting time - 345 minutes < 600 minutes
(as per 12269-1987)

21. TESTS ON FINE AGGREGATE
The physical properties of Fine aggregate are found from tests (as
per IS 2386-1963),
Fineness Modulus Of Fine Aggregate – 2.83
(Medium sand : 2.6-2.9)
Specific Gravity - 2.45
TESTS ON COARSE AGGREGATE
The physical properties of Coarse aggregate are found from tests
(as per IS 2386-1963),
Fineness Modulus of Coarse Aggregate 3.87 &
Specific Gravity - 2.78

22. Mix Design – M 30 Grade (as per IS 10262-1982)
Cement : Fine Aggregate : Coarse Aggregate
1 : 1.52 : 2.93
415 kg/m³ : 633 kg/m³ : 1215 kg/m³
Coarse Aggregates Proportion (55:45):
20 mm : 668 kg
12.5/10mm : 547 kg

23. EXPERIMENTAL RESULTS (Compression Test)

24. 0
10
20
30
40
50
60
0% 20% 30% 40% 50%
Compressive
strength
N/mm
2
GGBFS
7Days
14Days
28Days

25. 0
10
20
30
40
50
60
0% 5% 7.50% 10%
Compressive
Strength
N/mm
2
SILICA FUME
7Days
14Days
28Days

26. 25
30
35
40
45
50
55
60
0% 20% 30% 40% 50%
Compressive
strength
N/mm
2
GGBFS
7 Days (5%)
14 Days (5%)
28 Days (5%)
7 Days (7.5%)
14 Days (7.5%)
28 Days (7.5%)
7 Days (10%)
14 Days (10%)
28 Days (10%)

27. EXPERIMENTAL RESULTS (Split Tensile)

28. 2
2.5
3
3.5
4
4.5
5
5.5
6
0% 20% 30% 40% 50%
Spilt
Tensile
Strength
N/mm
2
GGBFS
7Days (5% SF)
14Days (5%SF)
28Days (5%SF)
7Days (7.5%SF)
14Days (7.5% SF)
28Days (7.5% SF)
7Days (10% SF)
14Days (10% SF)
28Days (10% SF)

29. EXPERIMENTAL RESULTS (Flexural Strength Test)

30. 4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
0% 20% 30% 40% 50%
Flexural
Tensile
Strength
N/mm
2
GGBFS
7Days (5% SF)
14Days (5% SF)
28Days (5% SF)
7Days (7.5% SF)
14Days (7.5% SF)
28Days (7.5% SF)
7Days (10% SF)
14Days (10% SF)
28Days (10% SF)

31. RESULTS & CONCLUSION
 Grade 30 mixes concrete were used for the design as these are
the most commonly used concrete grade.
 This designing of concrete mix was used to find out the high
strength concrete by replacing 20 %, 30 %, 40 %, 50 % of the
OPC cement by GGBFS & with 5 %, 7.5 % and 10 % of Silica Fume.
 The study was conducted in laboratory to investigate the
behavior of the concrete in terms of mechanical strengths as well
the workability properties.

32. CONCLUSION – Contd…
 The hardened concrete was tested for its compressive and tensile
strength with the combination of GGBFS and SF.
 The workability of each mix has been measured by using slump
test.
 Several concrete samples had been casted and cured by normal
curing and tested at the intervals of 7days, 14days and 28days.

33. THANK YOU