This document provides information on different types of special concretes including lightweight concrete, high density concrete, mass concrete, plum concrete, and fiber reinforced concrete. Lightweight concrete uses lightweight aggregates to reduce density. High density concrete uses heavy aggregates like iron ore to increase density above 2600 kg/m3. Mass concrete refers to large volume concrete placements where heat generation must be managed. Plum concrete includes large stones up to 300mm in a concrete mix. Fiber reinforced concrete uses discrete fibers to increase toughness and control cracking.

1. S.S. AGRAWAL
INSTITUTE OF
ENGINEERING AND
TECHNOLOGY
SPECIAL CONRETE
CIVIL ENGINEERING DEPARTMENT
GIUDED BY:
Mr. Amit Rana
Assistant Professor
PREPARED BY:
En. No. Name
151230106047 VERMA ASHISH.
151230106048 VASOYA KAUSHIK.
151230106049 PRAJAPATI VIMAL.
151230106050 VIRADIYA PARTH.
161233106001 ANADANI PIYUSH H.
1

2. CONTENS
• LIGHT WEIGHT CONCRETE
• HIGH DENSITY CONCRETE
• MASS CONCRETE
• PLUM CONRETE
• FIBER REINFORCED CONCRETE

3. Structural Lightweight Aggregate
Concrete

4. Light weight aggregate concrete
• The density of conventional concrete is in the order 2200 to 2600
kg/m³.
• This heavy self weight will make it uneconomical structural
material.
• There are two type of light weight aggregate concrete:-
(a) Natural light weight aggregate
(b) Artificial light weight aggregate
 Natural light weight aggregate
Pumice, scoria, Rice husk, saw dust.
 artificial light weight aggregate
sintered fly ash ,formed slag, bloated clay, artificial cinders,
expanded clay, slate, shale, coke breeze, expanded perlite , exfoliated
vermiculite.

5. • Mixing
– Similar to normal-weight concrete
– Aggregates may need presetting
• Workability
– Lightweight concrete exhibits better workability for a given
slump
• Finishing
– Generally starts earlier
• Curing
– Similar curing – added benefit of internal curing

6. Light weight concrete is achieved by
three different ways
• By replacing the normal mineral aggregate is known as ‘ light
weight aggregate concrete’.
• By introducing air bubbles in mortar is known as ‘ aerated
concrete’.
• By omitting sand fraction from the aggregate as ‘ no fines
concrete’.

7. High Density Concrete
 High Density=Heavyweight
 Density should be more than 2600 kg/m3
 Dens CRETE
 Offers more strength
 Can be used everywhere, in all construction practices
 Resistant to extreme weather

8. High Density concrete
• High density concrete is also known as ‘ Heavy weight concrete’.
• High density concrete is produced by replacing the ordinary
aggregate by a material of very much higher specific gravity.
• One of the more common natural aggregate is Barytes (barium
sulphate).its specific gravity of 4.1 and occurs as a natural rock with a
purity of about 95%.
• Another type of natural heavy weight aggregate is iron ore:
magnetite, limonite, hematite, goethite have been used.
• By using iron ore aggregate concrete with densities of between 3000
to 3900 kg/m³.
• Apart from biological hazards along with the nuclear reaction very
high temperature is also generated and shielding is necessary to
protect the electronic and other sensitive equipment's in the vicinity.
• High density concrete is also suites for preparing counter-balance
weight for lift bridges and ballast blocks for ships.

9. Main Components:
 Cement
--- Provides limited strength
--- Not that useful in high density concrete
--- Used as binding material
Water
Aggregates
Admixtures

10. Application:
 High density radiation shielding
 Precast blocks
 Mass concrete projects
 High density concrete applications columns
 Gravity seawall, coastal protection & breakwater structures
 Bridge counterweights
 Ballast for ocean vessels
 Off shore platforms noise and vibration dampening

11. Mass Concrete

12. • “An large volume of cast-in-place concrete with dimensions large
enough to require that measures be taken to cope with the generation
of heat and attendant volume change to minimize cracking.”
• Mass concrete includes not only low-cement-content concrete used
in dams and other massive structures but also moderate to high
cement content concrete in structural members of bridges and
buildings.
• As the interior concrete increases in temperature and expands, the
surface concrete may be cooling and contracting.
• The width and depth of cracks depends upon the temperature
differential, physical properties of the concrete, and the reinforcing
steel.
Mass concrete:

13. Casting of Mass concrete

14. Mass Concrete

15. Plum concrete
• The original idea of the use of aggregate as an inert filler can be
extended to the inclusion of large stones up to 300 mm size in a
normal concrete; thus the apparent yield of concrete for a given
amount of cement is increased this result concrete is called ‘ plum
concrete’.
• These large stones are called ‘plum’ and used in a large concrete
mass.
• They can be as big as 300mm size but should not be greater than 1/3
of the dimension to be concreted.
• The volume of plums should not exceed 20 to 30% of the total
volume of the finished concrete and they to be well dispersed
throughout the mass.
• Care must be taken to ensure that no air is trapped underneath the
stones.
• The plums must have no adhering coating. Otherwise discontinuities
between the plums and concret

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17. • Fibre reinforced concrete (FRC) may be defined as a composite
materials made with Portland cement, aggregate, and
incorporating discrete discontinuous fibres.
• 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.
• The fibre reinforcement may be 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.
Fibre reinforced concrete:

18. • 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.
3. However, as in compression, steel fibres do lead to major increases
in the post cracking behaviour or toughness of the composites.

19. • Application of SFRC:
The most common applications are
1. pavements
2. tunnel linings
3. pavements and slabs
4. shotcrete
5. 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.

20. Fibre reinforced concrete