Special concretes- Repair and rehabilitation of structures(RRS) - Concrete Technology

DEPARTMENT OF CIVIL ENGINEERING
CE6021-REPAIR AND REHABILITATION OF
STRUCTURE
UNIT III – SPECIAL CONCRETE
PRESENTATION BY
SHANMUGASUNDARAM N
ASSISTANT PROFESSOR
1/35CE6021-RRS/unit 3 by,Shanmugasundaram.N
12/4/2020

UNIT III
SPECIAL CONCRETE
Polymer concrete - Sulphur infiltrated concrete - Fiber
reinforced concrete - High strength concrete - High
performance concrete - Vacuum concrete - Self
compacting concrete - Geopolymer concrete - Reactive
powder concrete - Concrete made with industrial wastes.
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1. Polymer concrete
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Polymer concrete is part of
group of concretes that use
polymers to supplement or
replace cement as a binder.
The types include polymer-
impregnated concrete, polymer
concrete, and polymer-Portland-
cement concrete.

Polymer concrete
 In polymer concrete, thermosetting resins are used as the
principal polymer component due to their high thermal
stability and resistance to a wide variety of chemicals.
 Polymer concrete is also composed of aggregates that
include silica, quartz, granite, limestone, and other
high quality material.
 Polymer concrete may be used for new construction or
repairing of old concrete .
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Polymer concrete
The low permeability and corrosive resistance of polymer
concrete allows it to be used in
 swimming pools,
 sewer structure applications,
 drainage channels,
 electrolytic cells for base metal recovery, and
 other structures that contain liquids or corrosive
chemicals.
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Polymer concrete
 It is especially suited to the construction and
rehabilitation of manholes due to their ability to
withstand toxic and corrosive sewer gases and bacteria
commonly found in sewer systems.
 It can also be used as a replacement for asphalt
pavement, for higher durability and higher strength.
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Polymer concrete
 Polymer concrete has historically not been widely
adopted due to the high costs.
 Difficulty associated with traditional manufacturing
techniques.
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Type of Polymer Concrete
1. Polymer Impregnated Concrete (PIC).
2. Polymer Cement Concrete (PCC).
3. Polymer Concrete (PC).
4. Partially Impregnated and surface coated polymer concrete.
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Advantages
1. Rapid curing at ambient temperatures.
2. High tensile, flexural, and compressive strengths.
3. Good adhesion to most surfaces.
4. Good long-term durability with respect to freeze and thaw cycles.
5. Low permeability to water and aggressive solutions.
6. Good chemical resistance.
7. Good resistance against corrosion.
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Advantages
8. Lighter weight (only somewhat less dense than traditional
concrete, depending on the resin content of the mix)
9. May be vibrated to fill voids in forms.
10. Allows use of regular form-release agents (in some applications)
11. Dielectric
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Disadvantages
1. Product hard to manipulate with conventional tools such as drills
and presses due to its strength and density.
2. Recommend getting pre-modified product from the
manufacturer
3. Small boxes are more costly when compared to its precast
counterpart however pre cast concretes induction of stacking or
steel covers quickly bridge the gap.
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Using of polymer concrete on old
Concrete - video

2.Sulphur In Filtrated concrete
Why sulphur concrete ?
Sulphur concrete elements.mp4
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2.Sulphur In Filtrated concrete
 New types of composition
 Recently developed techniques
 Impregnating porous material
 Concrete with sulphur.
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Sulphur In Filtrated concrete
 Sulphur having strength impregnation as shown great improvement in
strength.
 Physical properties have been found to improve by several 100% and
large improvement in water impermeability.
 Resistance to corrosion have also been achieved.
 Some attempts sulphur as a binding material instead of cement.
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Manufacture method
 The quantity of sulphur used is also comparatively less and the
process is made economical.
 Sulphur is heated to bring it into molten condition to which
coarse and fine aggregate are poured and mixed together.
 This mixture give fairly good strength, acid resistance and other
chemical resistance.
 It proved to be costlier than ordinary cement concrete.
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 Its compressive strength of about 100mpa could be achieved in about 2
day time.
 Commercial sulphur of purity 99.9% are used.
 A large number of trial mix are mode to determine the best mix
proportion.
 The water cement ration of 0.7 or over as been adopted in all the trial.
 After 24 hours of moist curing the specimen is dried in heating cabin
ate for 24 hours in 1210c.
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 Then the dried specimen are placed in a container of molten sulphur at
1210c for 3 hours.
 The sulphur infiltrations can be employed in the precast industries.
This method of achieving
1) high strength can be used in the manufacture of precast roofing
element,
2) fencing post,
3) sewer pipes and
4) railway sleeper.
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 Sulphur infiltrated concrete should find considerable use in industrial
situation.
 High corrosion resistant concrete is required.
 This method cannot be conveniently applied to cast in place concrete.
 Sulphur infiltrated precast concrete unit is cheaper than commercial
concrete.
 The techniques are simple effective and in expansive.
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What type of concrete ?
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3.Fiber reinforced concrete
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Fiber reinforced concrete (FRC)
 Composite materials made with Portland cement, aggregate, and
incorporating discrete discontinuous fibres.
 Fibers can be in form of steel fiber, glass fiber, natural fiber , synthetic
fiber.
 The role of randomly distributes discontinuous fibres is to bridge
across the cracks that develop provides some post- cracking
“ductility”.
 The real contribution of the fibres is to increase the toughness of the
concrete under any type of loading.
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Fiber reinforced concrete (FRC)
 Used in the form of three – dimensionally randomly distributed fibres
throughout the structural member when the added advantages of the fibre to
shear resistance and crack control can be further utilised.
Tensile Strength:
1. Fibres aligned in the direction of the tensile stress may bring about very
large increases in direct tensile strength, as high as 1.33% for 5% of
smooth, straight steel fibres.
2. Thus, adding fibres merely to increase the direct tensile strength is probably
worthwhile
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Benefits
Main role of fibers is to bridge the cracks that develop in concrete and
increase the ductility of concrete elements.
Improvement on Post-Cracking behavior of concrete
Imparts more resistance to Impact load
controls plastic shrinkage cracking and drying shrinkage cracking
Lowers the permeability of concrete matrix and thus reduce the
bleeding of water
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Factors affecting the Properties of FRC
1. Volume of fibers
2. Aspect ratio of fiber
3. Orientation of fiber
4. Relative fiber matrix stiffness
1. Volume of Fibers
 Low volume fraction (less than 1%)
Used in slab and pavement that have large exposed surface leading
to high shrinkage cracking
 Moderate volume fraction(between 1 and 2 percent)
Used in Construction method such as Shortcrete & in Structures which
requires improved capacity against delamination, spalling & fatigue
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1. Volume of Fibers
 High volume fraction(greater than 2%)
Used in making high performance fiber reinforced composites
(HPFRC)
2. Aspect Ratio of fiber
 It is defined as ratio of length of fiber to it’s diameter (L/d).
 Increase in the aspect ratio upto 75,there is increase in relative
strength and toughness.
 Beyond 75 of aspect ratio there is decrease in aspect ratio and
toughness.
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3. Orientation of fibers
 Aligned in the direction perpendicular to load
 Aligned in the direction of load
 Randomly distribution of fibers
 It is observed that fibers aligned parallel to applied load offered more
tensile strength and toughness than randomly distributed or
perpendicular fibers.
4. Relative fiber matrix
 Modulus of elasticity of matrix must be less than of fibers for
efficient stress transfer.
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4. Relative fiber matrix
 Low modulus of fibers imparts more energy absorption while high modulus fibers
imparts strength and stiffness.
 Low modulus fibers e.g. Nylons and Polypropylene fibers
 High modulus fibers e.g. Steel, Glass, and Carbon fibers
Types fibers used in FRC
Steel Fiber Reinforced Concrete
Polypropylene Fiber Reinforced (PFR) concrete
Glass-Fiber Reinforced Concrete
Asbestos fibers
Carbon fibers and Other Natural fibers
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Steel Fiber Reinforced Concrete
Diameter Varying from 0.3-0.5 mm (IS:280-1976)
Length varying from 35-60 mm
Various shapes of steel fibers
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Application of FRC:
 Pavements
 Tunnel linings FRC-- Effect of fibre in the concrete
 Pavements and slabs
 Shotcrete
 Shotcrete also containing silica fume, airport pavements, bridge deck
slab repairs
 The fibres themselves are, unfortunately, relatively expensive; a 1%
steel fibre addition will approximately double the rate.
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4.High strength concrete
 High-strength concrete has a compressive strength greater
than 40 MPa.
 High strength concrete is made by lowering the water
cement (W/C) ratio to 0.35 or lower.
 Due to low w/c ratio it causes problem of placing ,to
overcome from this superplasticizer used
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4.High strength concrete
Compressive strength
 Normal structural concrete :20-40 MPa,
 High strength concrete(HSC): 40-100 MPa
 Ultra Strength concrete: 100-150 MPa, and
 Especial strength concrete > 150 MPa.
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Material for High Strength Concrete
1.Cement
 Almost any ASTM portland cement type can be used to obtain concrete
with compressive strength up to 60 MPa.
 In order to obtain higher strength mixtures while maintaining good
workability, it is necessary to study carefully the cement composition
and fineness.
ASTM-American Society for Testing and Materials
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2. Aggregates:
 In high-strength concrete, the aggregate plays an important role on the
strength of concrete.
 The higher the targeted compressive strength, the smaller the
maximum size of coarse aggregate.
 Up to 70 Mpa compressive strength can be produced with a good
coarse aggregate of a maximum size ranging from 20 to 28 mm.
 To produce 100 Mpa compressive strength aggregate with a maximum
size of 10 to 20 mm should be used.
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3.Supplementary Cementious Materials
 Fly ash, silica fume, or slag often mandatory
 Dosage rate 5% to 20% or higher by mass of cementing material.
Methods of making HSC
 Use of admixture
 Use of cementitious aggregate
 Seeding
 High speed slurry mixing
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Difference between NSC and HSC
 In normal strength concrete, the microcracks form when the compressive
stress reaches ~ 40% of the strength.
 The cracks interconnect when the stress reaches 80-90% of the strength.
 The fracture surface in NSC is rough.
 The fracture develops along the transition zone between the matrix
and aggregates.
 Fewer aggregate particles are broken.
 The fracture surface in HSC is smooth.
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Applications
 Use of HSC in column section decreases the column size.
 Use of HSC in column decreases amount of steel required for same
column.
 In high rise building, use of HSC increases the floor area for rental
purpose.
 In bridges, use of HSC reduces the number of beams supporting
the slab.
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Example of use of HSC in bridges
Vidya Sagar Setu Bridge,Kolkatta,India
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In Vidya Sagar Setu
Bridge,Kolkatta,India,
because of uses of HSC
instead of NSC increase the
span between two column and
strength

Example of use of HSC in bridges
Joingy Bridge,Paris
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In joingy bridge,NSC is
replaced by HSC because
of which volume of
concrete decreases by 30%.

5.High performance concrete
 High Performance Concrete (HPC) is a high-strength, ductile material
formulated by combining portland cement, silica fume, quartz flour,
fine silica sand, high-range water reducer, water, and steel or organic
fibers.
High Performance Concrete- A Robust Solution for Highway
Infrastructure.mp4
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5.High performance concrete
 Possessing high workability, high durability and high ultimate strength.
 As per ACI, HPC is defined as a concrete meeting special combination
of performance and uniformity requirements that cannot always be
achieved routinely using conventional constituents and normal mixing,
placing, and curing practices.
 The Strategic Highway Research Program (SHRP) in the United States
defined HPC for highway structures by three requirements, namely a
maximum w/cm, a minimum durability factor to cycles of freezing and
thawing (ASTM C 666, Method A), and a minimum early-age or
ultimate compressive strength.
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Characteristics of HPC
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1
• High early strength
• High strength
2
• High modulus of elasticity
• High abrasion resistance
3
• High durability and long life in severe environments
• Low permeability and diffusion

Characteristics of HPC
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4
• Resistance to chemical attack High resistance to
adverse climatic conditions
• Toughness and impact resistance
5
• Volume stability
• Ease of placement
6
• Compaction without segregation
• Inhibition of bacterial and mold growth

Four types of HPC were subsequently developed:
Very Early Strength (14 MPa in 6 hours),
High Early Strength (34 MPa in 24 hours),
Very High Strength (69 MPa in 28 days),
High Early Strength with Fiber- reinforcement.
Admixture:
a. Water reducing admixture is used
1.Increase workability 2. Reduces water and cement
content requirements 3. High early strength
b. Consists Lignosulfonic acid,carboxylic acids
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Materials used in HPC
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Material Primary Contribution/Desired
Property
Portland cement Cementing material / Durability
Blended cement
Cementing material /
Durability /
High
strength
Fly ash / Slag / Silica
fume
Calcined clay/ Metakaolin
Calcined shale
Superplasticizers Flowability
High-range water
reducers
Reduce water-cement ratio
Hydration control admix. Control setting

Materials used in HPC
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Material Primary contribution/Desired
property
Retarders Control setting
Accelerators Accelerate setting
Corrosion inhibitors Control steel corrosion
Water reducers Reduce cement and water
content
Shrinkage reducers Reduce shrinkage
ASR inhibitors Control alkali-silica activity
Improve workability/reduce paste
Polymer/latex
modifiers

Applications:
High density radiations shielding
Precast blocks
Mass concrete projects
High density concrete applications columns
Gravity seawall, costal production & break water structures
Bridge counterweights
Ballast for ocean vessels
Off shore platforms noise and vibration dampening
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6.Vacuum concrete
Vacuum concrete is the type of concrete in which the excess water
is removed for improving concrete strength.
The water is removed by use of vacuum mats connected to
a vacuum pump.
It was first invented by Billner in United states in 1935.
Reducing the final water-cement ratio of concrete before setting, to
control strength and other properties of concrete.
Tremix Vacuum Dewatering Pump.mp4
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Vacuum concrete
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Vacuum concrete
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Need for Vacuum concrete
 The chemical reaction of cement with water requires a water-cement
ratio of less than 0.38.
 But it is always taken more than 0.38.
 Workability is also important for concrete.
 Workability and high strength don’t go together as their requirements are
contradictory to each other.
 Vacuum concrete is the effective technique used to overcome this
contradiction of opposite requirements of workability and high
strength.
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Equipment's use in VacuumConcrete
Vacuum pump with hose pipe
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Water separator
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Filtering pad
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Screed board vibrator
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Power floater
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Power trowel
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Applications of VacuumConcrete
 Industrials floor sheds like cold storages
 Hydro power plants
 Bridges ports and harbour
 Cooling towers
Advantages of VacuumConcrete
 Increase of final strength of concrete by about 25%
 Sufficient decrease in permeability of concrete
 High density concrete
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Advantages of VacuumConcrete
 Increase of about 20% bond strength of concrete
 Appreciable reduction of time for final finishing
 Early removal of wall forms
 Increase in durability.
Disadvantages of VacuumConcrete
 High initial cost.
 Need trained labour.
 Need specific equipment.
 Need power consumption.
 The porosity of the concrete allows water, oil and grease to seep through,
consequently weakening the concrete.
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 Good quality of floors and pavements can be obtained.
 The compressive Strength can be increased by 25-45%.
 Durability of the floor can be increased.
 15-25% of water can be extracted out.
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7.Self compacting concrete
Self compacting concrete.mp4
Self-consolidating concrete or self-compacting concrete (commonly
abbreviated to SCC) is a concrete mix which has a low yield stress,
high deformability, good segregation resistance (prevents separation
of particles in the mix), and moderate viscosity (necessary to ensure
uniform suspension of solid particles during
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Self compacting concrete
 Self-compacting concrete (SCC) is an innovative concrete that does
not require vibration for placing and compaction.
 It is able to flow under its own.
 weight, completely filling formwork and achieving full compaction,
even in the presence of congested reinforcement.
 The hardened concrete is dense, homogeneous and has the same
engineering properties and durability as traditional vibrated
concrete.
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Self compacting concrete
 Very close to the Kolhapur there is project of steel industry, sand used for
the formation of mould when the moulds are opened the waste sand is
dumped for the filling the low lying areas while doing this the agriculture
areas is converted into barren area.
 Because there is no space for the waste other than the land filling. similar
case is in case of aluminium industry where red mud is concluded to be
waste, which contains lot amount of bauxite and that is why red mud is
also dump in the nearby areas here it is causing big threat for the society
and it is disturbing the eco system of the environment.
 So it is the need to use this particular otherwise waste material for the
constructive in such fashion in the case of concrete so that concrete which
became cost effective as well as eco-friendly.
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Type of Self compacting concrete
1. Powder type of self-compacting concrete: This is proportioned to
give the required self-compact ability by reducing the water-
powder ratio and provide adequate segregation resistance.
2. Viscosity agent type self-compacting concrete: This type is
proportioned to provide self-compaction by the use of viscosity
modifying admixture to provide segregation resistance.
3. Combination type self-compacting concrete: This type is
proportioned so as to obtain self compact ability mainly by reducing
the water powder ratio.
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Fresh SCC Properties:
 Filling ability (excellent deformability)
Passing ability (ability to pass reinforcement without blocking)
High resistance to segregation.
 It has been observed that the compressive strength of self compacting
concrete produced with the combination of admixtures goes on increasing
up to 2% addition of red mud.
 After 2% addition of red mud, the compressive strength starts decreasing,
i.e. the compressive strength of self-compacting concrete produced is
maximum when 2% red mud is added.
 The percentage increase in the compressive strength at 2% addition of
red mud is +9.11.
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Self Compacting Concrete Benefits
 Improved constructability.
 Labour reduction.
 Bond to reinforcing steel.
 Improved structural Integrity.
 Accelerates project schedules.
 Reduces skilled labour.
 Flows into complex forms.
 Reduces equipment wear.
 Minimizes voids on highly reinforced areas.
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Self Compacting Concrete Benefits
 Produces superior surface finishes.
 Superior strength and durability.
 Allows for easier pumping procedure.
 Fast placement without vibration or mechanical consolidation.
 Lowering noise levels produced by mechanical vibrators.
 Produces a uniform surface.
 Allows for innovative architectural features.
 It is recommended for deep sections or long-span applications.
 Produces a wider variety of placement techniques.
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Factors Affecting Self Compacting Concrete
 Using self-compacting concrete must not be used indiscriminately
(பாகுபாடுற்ற).
 These factors can affect the behaviour and performance of self-
compacting concrete:
 Hot weather.
 Long haul distances can reduce flow ability of self-compacting concrete.
 Delays on job site could affect the concrete mix design performance.
 Job site water addition to Self-Compacting Concrete may not always
yield the expected increase in flow ability and could cause stability
problems.
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How to reduce cement usage ?
 Partially replace the cement in concrete
EX: HIGH VOLUME FLYASH CONCRETE
 Develop alternativematerial
EX: GEOPOLYMER CONCRETE
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Why not OPC ?
 production is a major contributor to CO2 emissions as an estimated 5
TO 8 %of all human- generated atmospheric CO2 worldwide comes
from the concrete industry.
 Production of Portland cement is currently topping 2.6 billion tons per
year worldwide and growing at 5 percent annually.
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Why GEOPOLYMER?
 Geopolymer concrete has the potential to substantially curb CO2
emissions.
 produce a more durable infrastructure capable of design life
measured in hundreds ofyears.
 conserve hundreds of thousands of acres currently used for disposal of
coal combustion products.
 protect aquifers and surface bodies of fresh water via the elimination of
fly ash disposal sites.
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OPC vs GEOPOLYMER?
 Geopolymer concrete (GPC) using“fly ash”
 Greater corrosionresistance,
 Substantially higher fire resistance (upto 2400° F).
 High compressive and tensilestrengths
 Rapid strength gain, andlower shrinkage.
 Greenhouse gas reduction potential as muchas 90 percent when compared
with opc.
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8. Geopolymer concrete
 Hardened cementations paste made from fly ash and alkaline solution.
 Combines waste products into useful product.
 Setting mechanism depends on polymerization.
 Curing temp is between 60-90degree.
Geopolymer Concrete - Playing in the laboratory.mp4
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Constituents
 Source materials :
 Alumina-silicate
 Alkaline liquids
 Combination of sodium hydroxide (NaOH) or potassium
hydroxide (KOH) and sodium silicate or potassium silicate.
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Formation
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Process
 Alkaline solutions induce the Si and Al atoms in the source materials
,example fly ash to dissolve.
 Gel formation is assisted by applyingheat.
 Gel binds the aggregates ,and the un reacted source material to form the
Geopolymerconcrete.
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The aggregates are prepared in saturated-surface-dry (SSD)
Condition, and are kept in plastic buckets with lid

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The fly ash and the aggregates are first mixed together dry in 80-
litre capacity pan mix
Pan Mixer Used in the Manufacture of Geopolymer Concrete

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The liquid component of the mixture is then added to the dry
materials and the mixing continued usually for another four
minutes
Addition of Liquid Component

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The workability of fresh concrete was measured by means of
conventional slump test
Slump Measurement of Fresh GeopolymerConcrete

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Boundary between geopolymer binder, aggregate and
reinforcement

Compressive strength
 The compressive strengthof GEOPOLYMER concrete is about 1.5
times more than that of the compressive strength with the
ordinary Portland cement concrete, for the samemix.
 Similarly the Geopolymer Concrete showed good workability
as of the ordinary Portland Cement Concrete.
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Advandages
 Cutting the world’scarbon.
 The price of flyash is low.
 Better compressivestrength.
 Fire proof
 Low permeability.
 Eco-friendly.
 Excellent properties within both acid and salt environments.
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Applications
 Pre-cast concrete products like railway sleepers, electric power
poles, parking tilesetc.
 Marine structures due to resistance against chemical attacks
 Waste containments ( flyash)
 FUTURE use IN MAJOR PROJECTS
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 The reduced CO2 emissions of Geopolymer cements make them a good
alternative to Ordinary PortlandCement.
 Produces a substance that is comparable to or better than
traditional cements with respect to mostproperties.
 Geopolymer concrete has excellent properties within both acid and
salt environments
 Low-calcium fly ash-based geopolymer concrete has excellent
compressive strength and is suitable for Structural applications.
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9.Reactive power concrete
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Reactive powder concrete
Introduction
 RPC is the generic name for a class of cementious composite materials
developed by the technical division of Bouygues, in the early 1990s. It is
characterized by extremely good physical properties, particularly strength and
ductility
 A composite material & ultra high strength with mechanicalproperties.
 Mixture of fiber reinforced, super plasticized, silica fume, cement & quartz
sand with very low water cement ratio.
 Quartz sand used instead of ordinary aggregate, therefore increases compressive
strength
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RPC Composition
 RPC is able to obtain its improved properties by using a very dense mix,
consisting of fine particles and fibers.
 Low w/cm ratio : 0.16 to 0.24 (as low as 0.13)
 Type 20M (like type II) Portland cement (no C3A less HoH)
 Silica fume (25% by weight)
 Water, High dosages of super plasticizer
 Fine quartz sand (SG=2.75)
 Steel fibers (2.5-10% by volume) for toughening
 No rebar needed!
 Cured in steam bath for 48 hrs @ 190ºF (88ºC) after initial set, placed
under pressure at the molding stage
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RPC Mix and Placing
 Can be mixed and produced in a ready-mix truck and still have similar
strengths to those made in a central mixer.
 Self-placing, requires no internal vibration.
 Despite its composition, the large amount of super plasticizer still makes it
workable
Function parameters
 Give strength to aggregate
 Binding material
 Maximum reactivity during heat-treating
 Filling the voids
 Improve ductility
 Reduce water binding
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Principle
 Chard and Cheyrezy indicate the following principles for developing RPC
Elimination of coarse aggregates for enhancement of homogeneity
 Utilization of the pozzolanic properties of silica fume
 Optimization of the granular mixture for the benhan cement of compacted
density
 The optimal usage of super plasticizer to reduce w/c and improve workability
 Application of pressure (before and during setting) to improve compaction
 Post-set heat-treatment for the enhancement of the microstructure
 Addition of small-sized steel fibres to improve ductility
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Properties of RPC
 Compressive strength & Flexural strength
 Water absorption & Water permeability
 Resistance to chloride penetration
 Homogeneity & Compactness
 Micro-structure & Material ductility
 Almost no shrinkage or creep
 Light weight & Long life
 Aesthetic possibilities
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Properties of RPC
1. compressive strength
 Higher compressive strength than HPC
 It is a factor linked with durability of material.
 Maximum compressive strength of RPC is approximately 200MPa.
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Properties of RPC
2. Flexural Strength
 Plane RPC possess high flexural strength than HPC (Up to 100mpa)
 By introducing steel fibers, RPC can achieve high flexural strength.
3. WaterAbsorption
 The percentage of water absorption of RPC, however, is very low compared to
that of HPC.
 This quality of RPC is one among the desired properties of nuclear waste
containment materials.
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4. Water permeability
 It can be seen from the data that water permeability decreases with age for all
mixtures. 28th day water permeability of RPC is negligible when compared to that
of HPC (almost 7 times lower). As in the case of water absorption, the use of
fibres increases the surface permeability of both types of concrete.
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5. Resistance to chloride penetration
 Increases when heat curing is done in concrete.
 Heat cured RPC show higher value than normal cured RPC.
 This property of RPC enhances its suitability for use in nuclear waste
containment structures.
6. Homogeneity
 Improved by eliminating all coarse aggregates
 Dry components for use in RPC is less than 600 micro meter.
7. Compactness
 Application of pressure before and during concrete setting period.
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8. Microstructure:
 Microstructure of the cement hydrate can be changed by applying heat treatment
during curing.
9. material ductility:
 Material ductility can be improved through the addition of short steelfibres.
RPC Applications:
 RPC's properties, especially its high strength characteristic suggests the
material might be good for things needing lower structural weight, greater
structural spans, and even in seismic regions, it outperforms normal concrete.
Below are a few examples of real-world applications, though the future
possibilities are endless.
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RPC Applications:
 First bridge that used RPC was a pedestrian bridge in Sherbrooke, Quebec,
Canada. (33,000 psi~230MPa) It was used during the early days of RPC
production. Has prompted bridge building in NorthAmerica, Europe,Australia,
andAsia. (PSI- Pound-force per square inch)
 Portugal has used it for seawall anchors.
 Austrailia has used it in a vehicular bridge.
 France has used it in building power plants.
 Qinghai ( China) - Tibet Railway Bridge
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RPC Applications:
 Shawnessy Light Rail Transit Station
 Basically, structures needing light and thin components, things like roofs for
stadiums, long bridge spans, and anything that needs extra safety or security
such as blast resistantstructures
Sher brooke pedestrain bridge - canada
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Benefits
 It has the potential to structurally compete with steel.
 Superior strength combined with higher shear capacity result in significant dead
load reduction.
 RPC can be used to resist all but direct primary tensile stress.
 Improved seismic performance by reducing inertia load with lighter member.
 Low & non-interconnected porosity diminishes mass transfer, making
penetration of liquid/gas non-existent.
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Limitations of RPC
 In a typical RPC mixture design, the least costly components of conventional
concrete are basically eliminated or replaced by more expensive elements.
 No code
 The fine sand used in RPC becomes equivalent to the coarse aggregate of
conventional concrete, the Portland cement plays the role of the fine aggregate
and the silica fume that of the cement.
 The mineral component optimization alone results in a substantial increase in
cost over and above that of conventional concrete (5 to 10 times higher than
HPC)
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Limitations of RPC
 RPC should be used in areas where substantial weight savings can be realized and
where some of the remarkable characteristics of the material can be fully utilized.
 Owing to its high durability, RPC can even replace steel in compression members where
durability issues are at stake (e.g. in marine condition).
 Since RPC is in its developing stage, the long-term properties are not known.
CONCLUSION
 It has immense potential in construction due to its mechanical strength and durability
aspects.
 RPC has ultra dense microstructure giving advantages of water proofing and
durability characteristics
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10.Concrete made with industrial waste
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FLYASH RED MUD
METAKAOLIN
GGBS MICROSILICA RHA

Indroduction:
 The consumption of natural aggregates of all types has been increasing in recent
years in most countries owing to rapid industrialization.
Due to increased construction activities in India, availability of natural fine
aggregates are depleting by each passing day. The continued extraction of natural
aggregates leads to serious environmental problem including landslides.
 Using industrial waste products as either cement additives or alternate fuels, it is
possible to reduce the quantity of raw materials and fossil fuels used to produce
cement.
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Indroduction:
 The use of industrial by-products diverts the material from the waste stream,
reduce the energy used in processing virgin materials, use of virgin materials and
decreases pollution.
 Besides industrial waste offering environmental advantages, it also improves the
performance (HSC and HPC) and quality of concrete which is the need of hour for
Most problems of century including Earthquake resistance and Durability.
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Indroduction:
 Utilization in concrete – a best alternative since it uses up Fly ash, Red mud,
Silica fume, Rice-husk ash or GGBS for OPC.
 It helps to put off Global Warming but utilizes the waste materials efficiently
thereby reducing the risk of waste disposal and at same hand, safeguards
dwindling natural resources.
 The role of a Civil Engineer is to reduce cement consumption through the use
of supplementary materials.
 Hoping this simple initiative will add water to the burning fire and it will kindle
the spirit of young Civil Engineers to use eco-friendly construction materials in
this present scenario.
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Fly ash - non-combusted by-product of coal-fired power plants. During
combustion, the coal's mineral impurities such as clay, feldspar, quartz and shale
fuse in suspension and are carried away from the combustion chamber by the
exhaust gases. Such fused material cools and solidifies into spherical glassy
particles called fly ash. Fly ash is a finely divided powder resembling Portland
cement consisting mostly of SiO2.
Red mud - majorindustrial waste by Bayer process for the extraction of alumina.
Characterized by strong alkalinity due to presence of excessive amount of
dissolved NaOH. The red color is by the oxidized Fe present, which can make up
to 60% of mass of the red mud. In addition to Fe, the other dominant particles
include silica, unleached residual Al, andTiO2.
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 Disposal becomes a huge problem due to the presence of high pH, heavy metals
and radioactivity.
 Hence new technologies utilizing red mud are gently needed, besides the use in
of GPC.
Kaolinite – clay mineral with the chemical composition Al2Si2O5(OH)4, which
means each particle has one tetrahedral silica layer and one octahedral alumina
layer.
It is a soft mineral produced by the chemical weathering of aluminum silicate
minerals like feldspar.
Rocks that arerich in Kaolinite are also known as china clay, white clay, or kaolin.
Metakaolin is a dehydroxylated form of the clay mineral Kaolinite in the
temperature range of 500- 800°C. It is a highly pozzolanic.
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Ground-granulated blast-furnace slag (GGBS) - obtained by quenching molten
iron slag (உருகிய இரும்புக் கசடு வெடிப்பு உலை) from a blast furnace in water or
steam, to produce a glassy, granular product that is then dried and ground into a
fine powder.
 The main components of blast furnace slag are CaO (30-50%), SiO2 (28- 38%),
Al2O3 (8-24%) and MgO (1-18%).
 GGBS has now effectively replaced sulfate-resisting Portland cement (SRPC)
on the market for sulfate resistance because of its superior performance and greatly
reduced cost compared to SRPC.
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Silica fume - also known as microsilica, is an amorphous polymorph of silicon
dioxide, silica.
 It is an ultrafine powder collected as a by-product of the silicon and ferrosilicon
alloy production.
 It is an ultrafine material with spherical particles less than 1 µm in diameter, the
average being about 0.15 µm.
 This makes it approximately 100 times smaller than the average cement particle
which makes it suitable as pozzolanic material for high performance concrete.
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Rice husk Ash (RHA) - Rice husk also called rice hull, is the hard protecting
covering of grains of rice, which is a by-product generally obtained from milling
process of rice.
 The RHA is generated after burning the rice husk in the boiler, which is
collected from the particulate collection equipment.
 It is highly porous, lightweight and contains silica in high content (90 – 95%).
At present, disposal of RHA is dumping on waste land, creating land dereliction
problems. Since amount of RHA generated is in plenty, an effective way of
disposal of RHA is needed urgently.
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Conclusion
 From the literature reviews it is concluded that
 Micro silica can be added at a rate of 5-15% by weight of cement
 Red Mud can be used up to 30%.
 Fly Ash and GGBS can be used upto 100% in GPC RHA can be
replaced upto 20%.
 The performance of various by-products in concrete can be listed as
follows
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Other concretes
High Volume Fly Ash Concrete, Silica fume concrete, GGBS,
Slag based concrete, Ternary blend concrete, Light weight
concrete, Coloured Concrete, Pervious Concrete, Water-proof
Concrete,, Temperature Controlled Concrete, Ferro cement,
Ready mix concrete, Shotcrete tech, Sifcon, Etc...
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12/4/2020

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