The document discusses bendable or engineered cementitious composite (ECC) concrete. It is a type of fiber-reinforced concrete that is ductile and crack-resistant. ECC concrete uses microfibers, a slick coating on the fibers, fine sand, and superplasticizers. It bends like metal and is stronger and more durable than regular concrete. Structures made of ECC concrete are earthquake and crack resistant. Examples of uses include earthquake-proof buildings, flexible concrete canvases for military use, and more durable bridges and roads.
4. CONTENT
INTRODUCTION
WHAT IS BENDABLE CONCRTE ?
MATERIALS USED IN BENDABLE CONCRETE
ADVANTAGES OF BENDABLE CONCRETE
DISADVANTAGES OF BENDABLE CONCRETE
USES OF ECC OR BENDABLE CONCRETE
SOME OF THE STRUCTURES CONSTRUCTED BY USING
BENDABLE CONCRETE
5. INTRODUCTION
Concrete is widely used in today’s construction industry. It
has good load bearing capacity. It can take
the compressive load very effectively. But the main problem
with the traditional concrete is that it cannot take much
tensile stresses. It fails under the tensile load. The bendable
concrete is a good substitute for this problem.
6. Bendable concrete is class of ultra-ductile fiber
reinforced cementitious composites, characterized
by high ductility and tight crack width control. This
material is capable to exhibit considerably enhanced
flexibility.
8. It is special type of concrete that can take the bending
stresses. It consists of special type of materials that makes it
flexible.
It was developed by the Professor Victor Li at the University
of Michigan.
Its engineering name is Engineered Cementitious
Composite(ECC)
It exhibits the property of a ductile material instead of a
brittle material which is shown by the conventional
concrete.
10. 1. FIBRES REINFORCEMENT
For giving the concrete flexibility we have to alter the material of the
conventional concrete.
In the bendable concrete we eliminate the coarse aggregate. Instead of
that we use the fibres that are used in the fibre reinforced concrete such
as silica fibres, glass fibres, steel fibres, asbestos fibers, polyvinyl
alcohol fibers, etc.
The micro fibres provide the flexibility to the concrete. It also act as
a reinforcement material in the concrete.
13. 2. SLICK COATING (ANTI-FRICTION COATING)
Additionally, the slick coating (anti-frictional coating) is
provided so that the fibers particles can slide over one another
and does not have the friction which may result into the cracks
in concrete.
This tendency of slipping of fibers over one another helps the
concrete to minimize the crack and provide flexibility to the
concrete. The normal cement can be used for the concrete.
14.
15. 3. FINE SAND
The fine silica sand is suitable for the bendable concrete which
is used in the water treatment plant but if it is not available the
normal sand can be used but it may effects the strength and
flexibility of concrete. fly ash, silica fume, blast furnace slag
can also be used in the concrete.
16.
17. 4. SUPERPLASTICIZER
Polycarboxylated ether, lignosulfonates, lignin, napthalene or
melamine formal dehyde sulphonate(any one) is used in the
concrete for increasing the workability of the concrete. Latex
can also be used in the concrete for improving its flexibility.
20. The bendable concrete has the ability to bend like a metal
It is more stronger, more durable, and lasts longer than
conventional concrete
It has a self-healing property that it can heal itself by using
carbon dioxide and rainwater
It is not brittle like a glass
It is more resistant to cracking
It does not emit that amount of harmful gases as compared to
conventional concrete.
21. The bendable concrete is approximately 20 - 40% lighter
The use of steel reinforcement is reduces and can be eliminated
It reduces the cost of the project
It can be used as precast concrete.
23. It has a high initial cost as compared to conventional concrete.
It requires skilled labour for its construction.
It needs some special type of materials which can be difficult to
find in some areas.
Its quality depends upon the material used and the condition
under which it is made.
Its compressive strength can be lesser than the conventional
concrete.
24. SPECIAL FEATURES OF BENDABLE CONCRETE
The bending strength or tensile capacity of bendable concrete is
in the range of 10 to 15 MPa and compressive strength is up to
70 MPa.
It has a self-healing property as the cement particles make
reaction with the rain water and makes some complex product
that expands and fill the microcracks that are developed in the
bendable concrete.
25. The bendable concrete is proved to be lighter and also proved to
be 500 times more bendable than normal concrete.
Its ultimate tensile strain capacity is 3 to 5 %.
The strain capacity in bendable concrete is 300 times more than
conventional concrete. Due to this the concrete is act like a
flexible material such as metal.
28. EARTHQUAKE RESISTANCE BUILDING
The structure made with the bendable concrete can take more
tensile stresses that it does not break down due to the vibration
caused by the earthquake. In Japan a 60 floor is under
construction which uses this concrete.
29. CONCRETE CANVAS
The concrete canvas can also be made with the
bendable concrete. The concrete canvas is stronger and
durable than the normal canvas. It can be used in the
military area.
31. FOR ROADS & BRIDGES
It can be used in roads and bridges. With the use of bendable
concrete in roads and bridges there is no need of joints such as
expansion joint, contraction joint as the concrete is itself have
the ability to change its shape. More over the bridges and roads
are more durable and has low repair cost.
32. SOME OF THE STRUCTURES CONSTRUCTED
BY USING BENDABLE CONCRETE
