SIFCON (Slurry Infiltrated Fibre Concrete) is a unique construction material with high strength and ductility due to a phenomenon called "fiber-lock". It consists of a cementitious slurry matrix reinforced with steel fibers. The slurry has no coarse aggregates but a high cement and fine sand content. Factors like slurry strength, fiber volume and alignment affect its properties. SIFCON has excellent durability and energy absorption and is used in applications like pavements, bridges, and blast-resistant structures.

1. SIFCON
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2. SIFCON
Slurry Infiltrated Fibre Concrete (SIFCON) is unique construction material possessing
high strength as well as large ductility and far excellent potential for structural
applications when accidental or abnormal loads are encountered during service.
• SIFCON exhibit new behavioral phenomenon, known as “Fiber-lock” which
believed to be responsible for its outstanding stress-strain properties. The matrix of
SIFCON has no coarse aggregates, but high cementitious content. However, it may
contain fine (or) coarse sand and additives such as fly ash, micro silica and latex
emulsions.
• The unit weight of SIFCON is typically higher than concrete and normal FRC
because of the relatively heavy weight of the high fiber content. The unit weight
increase is almost linearly proportional to the fiber content.
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3. SIFCON
Factors Affecting SIFCON Efficiency
The following factors affect the strength of SIFCON and the ultimate strength,
ductility and energy absorption are all affected by fiber alignment.
i. Slurry strength
ii. Fiber volume
iii. Fiber alignment
iv. Fiber type
Advantages of SIFCON
i. SIFCON possess excellent durability, energy absorption capacity, impact and
abrasion resistance and toughness.
ii. Modulus of elasticity (E) values for SIFCON specimens is more compared with
plain concrete.
iii. SIFCON exhibits high ductility.
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4. SIFCON
iv. The limitation in SFRC that is balling problem of steel fibers with increase in fiber
volume is overcomes by SIFCON, because of its fiber alignment.
v. Deflection for SIFCON will be very less compared to conventional and will act as
rigid body.
DISADVANTAGES OF SIFCON
Inspite of unique properties of SIFCON it doesn’t have much limitations. Uniformity
and quality control of fiber distribution in addition to high placement cost associated
with manual addition of fibers, restricted wide applications of these composites.
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5. SIFCON
MATERIALS USED or CONSTITUENT MATERIALS
SIFCON constitutes several materials like, cement, sand, fly ash, steel fiber, high range
water reducing admixture called CONPLAST SP- 430.
MIX PROPORTION
In general, proportions of cement and sand generally used for making SIFCON are
1:1, Fly ash equal to 50%by weight of cement is used in mix. w/c is 0.45 and super
plasticizers varies from 2% to 5% of weight of cement can be used. The percentage of
fibers by volume can be where from 6% to 12% used. Sand which passes through 600
μ and retains 300 μ can be selected.
The process of making SIFCON is different, because of high steel fiber content. While
in SFRC the steel fibers are mixed intimately with wet (or) dry mix of concrete, prior
to mix being poured into forms. SIFCON is made by infiltrating low viscosity cement
slurry in to a bed of steel fibers “pre packed” in forms (or) moulds. 36

6. SIFCON
USAGE /APPLICATION AREA
SIFCON has properties like ductility, crack resistance, penetration and impact
resistance very high compared to other materials like SFRC, concrete it is best suited
to applications in following areas:-
• Pavement rehabilitation and pre cast concrete products.
• Overlays, bridge decks and protective revetments.
• Seismic and explosive resistant structures.
• Security concrete applications.(safety vaults, strong rooms)
• Refractory applications. (soak-pit covers, furnace lintels, saddle piers )
• Sea protective works.
• Military applications such as anti-missile hangers, under ground shelters.
• Aerospace launching platforms.
• Repair, rehabilitation and strengthening of structures.
• Concrete mega structures like offshore and long span structures, solar towers.
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7. SIFCON
ENGINEERING PROPERTIES
The mechanical properties is of SIFCON depend on the fibre and concrete slurry
properties such as fibre type, volume, alignment, compressive strength and modulus
of elasticity of slurry. The properties are:
1. Compressive strength
2. Split tensile strength and
3. Flexural strength.
Compressive strength of SIFCON mixes increases with increasing the percentage
volume of fiber. It can be observed that the 28 day compressive strength of SIFCON-
12 is considerably higher to other SIFCON mixes. Hence, it can be concluded that
addition of locally available low tensile steel fibers also contribute to compressive
strength of the mix.
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8. SIFCON
ENGINEERING PROPERTIES (contd….)
• The tensile strength of SIFCON is higher than M30 grade concrete. It was observed,
there is an increase in the compression, tension and flexural strength with an
increase in the volume of steel fibers fraction. 12% addition of steel fibers increases
the strength about 36.2% when compared to conventional concrete.
• Flexural strength of SIFCON is 5.5 N/mm2 for using 12% volume fraction of Steel
fiber. If using 14 % of steel fiber this value also increasing
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9. POLYMER CONCRETE
POLYMER CONCRETE (PC)
• It is the latest technique which involves impregnation of monomer and subsequent
polymerization to reduce the inherent porosity of the concrete and improve the
strength and other properties of concrete.
• The main technique in producing PC is to minimize void volume in the aggregate
mass so as to reduce the quantity of polymer needed for binding the aggregates.
This is achieved by properly grading and mixing the aggregates to attain the
maximum density and minimum void volume.
• Purpose of developing PC/ Advantages of PC are to minimize voids and increase the
resistance to chemical attack.
• The strength obtained by PC can be as high as 140 Mpa with a short curing period.
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10. POLYMER CONCRETE
POLYMER CONCRETE (PC) (contd….)
Types of polymer concrete
i. Polymer Impregnated Concrete (PIC)
ii. Polymer Cement Concrete (PCC)
iii. Partially Impregnated and surface coated polymer concrete.
Polymer Cement Concrete: It is made by mixing cement, aggregates, water and
monomer. Such plastic mixture is cast in moulds, cured, dried and polymerised. The
monomers that are used in PCC are:
i. Polyster-styrene
ii. Epoxy-styrene
iii. Furans
iv. Vinylidene Chloride
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11. SIFCON
QUESTIONS
1. Define SIFCON. Mention the materials used.
2. What are the factors affecting the efficiency of SIFCON?
3. Mention applications of SIFCON.
4. What are the advantages and disadvantages of SIFCON?
5. List the properties of SIFCON.
6. Enumerate mix proportions for SIFCON
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