2. WHAT IS CONCRETE ?
Concrete is an essential material used in the
construction of different types of structures.
Portland cement is the most common type of
cement in general usage.
It is a basic ingredient of concrete, mortar and
Combining water with a cementitious material forms
a cement paste by the process of hydration.
The cement paste glues the aggregate together,
fills voids within it, and makes it flow more.
Fine and coarse aggregates make up the bulk of a
Sand, natural gravel, and crushed stone are used
mainly for this purpose.
Fine aggregate Coarse aggregete
7. CHEMICAL ADMIXTURES:
Chemical admixtures are materials in the form of
powder or fluids that are added to the concrete to
enhance the properties of the concrete.
The common types of admixtures are as follows:
Air entraining agents
8. MINERAL ADMIXTURES:
Inorganic materials that have latent hydraulic properties,
these very fine-grained materials are added to the
concrete mix to improve the properties of concrete.
Ground granulated blast furnace slag
9. NORMAL CONCRETE:
The normal concrete is prepared using only:
Concrete has relatively high compressive strength
but significantly lower tensile strength.
Concrete has a very low coefficient of thermal
All concrete structures will changes, due to
shrinkage and tension.
10. DEMERITS OF NORMAL CONCRETE:
Compared to other binding materials, the tensile
strength of concreter is relatively low.
Concrete is less ductile.
The setting time of the concrete is very quick.
Due to these defects the admixtures can be used to
enhance the properties.
11. ADVANCES IN CONCRETE TECHNOLOGY:
There have been a number of advances in new
concrete technology in the past ten years.
Fresh concrete Hardened concrete
12. HIGH PERFORMANCE CONCRETE:
The latest new concrete technology is high performance
concrete (HPC), ultra high performance concrete, and
geo polymer concrete.
Recycled materials contained in these concrete is
ground granulated blast furnace slag,
Reduction in the usage of cement,
Reduction in the creation of carbon dioxide emissions,
14. GREEN CONCRETE:
Green concrete is environmental friendly concrete.
Concrete that uses less energy in its production and
produces less carbon dioxide than normal concrete is
called green concrete.
Usually the carbon dioxide is present in the cement and
in the aggregate.
15. COMPOSITION OF GREEN CONCRETE:
40% of Portland cement,
25% of ultra fine slag,
25% of ultra fine fly ash and 10% of silica fume,
4% volume fraction of steel fiber.
saving energy and saves money
Increased concrete industry’s use of waste products by 20%
NO environmental pollution and sustainable development.
Green concrete requires less maintenance and repairs.
Green concrete having better workability than conventional
Good thermal resistant and fire resistant.
The main limitation or disadvantage of using green concrete
is that the structures which are constructed using green
concrete have less life than the structures constructed by the
The split tensile strength of the green concrete is less than
the conventional concrete.
Sometimes corrosion in the steel bars can also occur if the
aggregates used are not free from corrosion leading agents.
18. FEATURES OF GREEN CONCRETE:
The green concrete must have the following
Optimizes use of available materials
Enhanced cohesion workability
Durability-Better life time
Reduced carbon foot print
No increase in cost
LEED India Certification
20. SUITABILITY OF CONCRETE:
Reduce the dead weight of the concrete
Good thermal and fire resistant
Improve damping resistance of buildings
Reduction of concrete Industry’s CO2 emissions by 30%
Increased concrete industries’ use of waste products by
No environmental pollution and sustainable development
Green concrete requires less maintanance and repairs.
Hence cement plays a key role over past 100 years, when
human started construction.
Cement is the most building material used by human.
Cement has more compression and steel has more
No other material is present , which can replace cement.