Presentation (prc I) Consistency , final & initial setting time test
1. Plain and Reinforced cementPlain and Reinforced cement
concrete (PRC-I)concrete (PRC-I)
Portland cement , Test on cement
& concrete
2. What is Concrete?
• Concrete is a mixture of cement, fine and coarse
aggregate.
• Divided into two parts PCC and RCC
• Mixture of cement, sand and coarse aggregate
without any reinforcement is known as PCC(Plain
cement concrete).
• Mixture of cement, sand and coarse aggregate
with reinforcement is known as RCC(Reinforced
cement concrete).
3. Importance in Civil Engineering
• Concrete is widely used for making
architectural structures, foundations,
brick/block walls, pavements,
bridges/overpasses, highways, runways,
parking structures, dams, pools/reservoirs,
pipes, footings , fences and poles and even
boats.
• Concrete is used in large quantities almost
everywhere mankind has a need for
infrastructure.
4. Some Concrete Structures
• Burj Kalifa tallest Building in the
world.
• Location: Dubai, United Arab
Emirates
• Time to build: 6 years
• Cost: USD $1.5 billion
• Height: 829.8m (2,722ft)
• (228.8m higher than the second
tallest building in the world)
• Floor count: 163 floors
5. • World’s Tallest Bridge in The world.
• Location: Millau-Creissels, France
• Time to build: 3 years
• Cost: USD $524m (€394m)
• Height: 343m (1,125ft)
6. • Three gorges Dam , World’s
Largest power station.
• Location: Sandouping, Yiling,
Hubei
• Time to build: 14 years
• Cost: USD $37 billion (¥180
billion)
• Original estimated cost: USD
$6 billion (¥20 billion)
• Height: 181m (594ft)
7. What is cement ?
• Cement is a fine powder,
• When mixed with water and allowed to set and
harden can join different components or members
together to give a mechanically strong structure.
• The percentage of cement in concrete is around
15%,
8. Role of Cement in Concrete
• Cement is binding material in the cement concrete.
• It fills up voids existing in the fine aggregate and
makes the concrete impermeable.
• It provides strength to concrete on setting and
hardening.
• The role of cement is very important in the strength
and durability of concrete.
9. Overview of Portland Cement
• Dry powder of very fine particles
• forms a paste when mixed with water
• chemical reaction-Hydration
• glue
• paste coats all the aggregates together
• hardens and forms a solid mass.
OR
• Ordinary Portland Cement is a controlled
blend of calcium silicates, aluminates
and ferrate, which is ground to a fine
powder with gypsum and other materials
11. Type I - NormalType I - Normal
Type III - High Early Type IV - Low Heat of Hydration
12. Difference b/w Hydraulic & Non
Hydraulic Cement
Hydraulic cement,
•Portland cement
•Cement that hardens under water
•Made by heating limestone and clay in a kiln and pulverizing
the result
Non Hydraulic cement,
•Cement which cannot harden while in contact with water.
•Made by using materials such as non-hydraulic lime and
gypsum plasters and oxychloride, which has liquid properties.
13. Tests On Cement
• There are many tests of Cement But in our
studies:
• Consistency Test
• Initial setting time
• Final setting Time
14. Consistency Test
• Consistency means amount of water needed to
prepare a plastic mix.
• Consistency test is done using Vicat's apparatus.
• The standard consistency of a cement paste is
defined as that consistency which will permit the
vicat plunger to penetrate to a point 5 to 7mm
from the bottom of the vicat mould.
15. About Vicat’s Apparatus
• It consists of the following:
• Ruler starting from 40 mm(which is the
height of the mould).
• The Mould.
• Non-porous plate.
• The plunger.
• Note: The depth is always measured
from the bottom of the mould.
16. • (Note):-For making the normal consistence of standard paste
we use a plunger with 10mm diameter.
17. Why we do Consistency Test ?
• Consistency test is used to find the amount of
water to be mixed with Cement.
• It is necessary to find the consistency because
amount of water present in the cement paste
may affect the setting time.
• Consistency of cement should be less than
30%
18. Initial & Final Setting Time Test
On Cement
Initial Set
•Time from moment water is added until the
paste ceases to be fluid and plastic.
Final Set
•Time from moment water is added for the
paste to acquire a certain degree of hardness.
19. Initial & Final Setting Time Test
On Cement
• The time of setting of the hydraulic cement Is done
by using VICAT needle apparatus.
• Needle Sizes
• For Initial Setting Time
• 1mm x 1mm cross-section
• 50mm length
• For Final Setting Time
• 1mm2 cross-section and 1mm deep inner needle
• 5mm diameter outer metal attachment
20. Why Initial & Final Setting Time
Is necessary ?
• It is very important to know the setting times.
• Knowing the initial setting time is important in
estimating free time for
• Mixing,
• transporting,
• placing,
• compaction
• and shaping of cement paste
21. Why Initial & Final Setting Time
Is necessary ?
• Knowledge of final setting time of cement is
necessary as well :
• After initial setting of cement Concrete starts
gaining strength and harden So we have to
know approximate final setting time of
cement.
• After final setting of cement Strength of
concrete can also be calculated.
• Final setting time also affects the strength and
durability of concrete.