Unit 1 cement

Gurukul Education Society’s Institute of
Engineering & Technology
Subject : Concrete Technology (CTE) Semester : Third
Subject Code : 22305 Year : 2nd (2020-21)
Subject Teacher: Prof. K. S. Somase Scheme : I
Department of Civil Engineering
Concrete Technology
Unit 1- Cement
By
Prof. K. S. Somase
(BE-Civil Engg)

Unit : 1 (Topics and Subtopics)
Civil Engineering Department
Gurukul Education Society’s Institute of Engineering & Technology
by : prof: k.s.somase
1
UNIT

• Introduction
• Cement- Cement is a substance acts as a binding agent
for materials. It is obtained by burning the mixture of
calcareous material such as limestone and argillaceous
materials such as clay at a high temperature.
• It is defined as the bonding material having cohesive
and adhesive properties which makes it capable to unite
the different construction materials and form the
compacted assembly.
• The Most Common type of cement is Ordinary Portland Cement
• There are two main constituents in Portland cement:
 Argillaceous materials – clay or shale.
 Calcareous materials – Limestone ,Calcium carbonate.
Concrete Technology
Unit 1 - Cement
1
UNIT

 It is an excellent binding material.
 Gives strength to masonry.
 Possesses a good plasticity.
 Offers a good resistance to moisture.
 Easily workable.
 It hardens quickly after addition of water.
 The color of cement should be uniform.
 Cement should be free from lumps.
 Cement should feel smooth when touched or rubbed in
between fingers.
Properties of cement
1
UNIT

Sr.No. Name Of Compound Formula Composition
(%)
1. Lime CaO 62 - 65
2. Silica SiO2 17 - 25
3. Alumina Al2O3 3 - 8
4. Iron Oxide Fe2O3 0.5 - 6
5. Magnesia MgO 0.1 – 4
6. Sulphur Trioxide SO3 2 – 3.5
7. Soda And Potash Na2O+K2O 0.2– 1
1.1 Chemical Constituents of OPC
1
UNIT

1. Lime (62-65%)
 Imparts strength and soundness (volume)
 Excess- makes cement unsound, causes it to set quickly.
 Deficiency-reduces strength of cement causes it to set quickly.
2. Silica(17-25%)
• Imparts strength to cement
• Excess – increases strength of cement But increases setting time of cement
3. Alumina(3-8%)
• Imparts strength to cement
• Excess – increases strength of cement But increases setting time of cement
• Reduce the Clinkering temperature of cement.
Functions On Different Constituents
of Cement
1
UNIT

4. Iron Oxide (0.5 – 6%)
 Impart color, strength and hardness to cement.
 It induces reddish brown tint to the cement
5. Magnesia (0.1 – 4%)
• Imparts strength and colour to cement (Yellowish Tint)
• Excess –Make cement unsound
6. Sulphur Trioxide (2 – 3.5%)
• It is also responsible for imparting Soundness.
7. Soda And Potash (Alkalies) (0.2– 1%)
• It causes efflorescence and staning of stucture
• Alkalies react with water and white gray spot are formed.
Functions On Different Constituents
of Cement
1
UNIT

Sr.
No Name Of Compound Formula Short Form
1. Tricalcium silicate 3CaO.Sio2 C3S
2. Dicalcium Silicate 2Cao.Sio2 C2S
3. Tricalcium Aluminate 3Cao.Al2O3 C3A
4. Tetracalcium Alumino
ferrite
4CaO.Al2O3.Fe2O3 C4AF
Water reacts with ingredients of cement chemically, resulting in
formation of complex chemical compounds termed as bogues
compound, which are not formed simultaneously.
Bogue’s Compounds
1
UNIT

1. Tricalcium silicate-
• 45-85% by weight
• Formed within a week of addition of water in cement.
• Responsible for development of early strength of cement in initial
stages.
2. Dicalcium Silicate-
• It is formed very slowly after addition of water in cement and man
require a year of so for its formation
• It is responsible for progressive strength of cement in later stages.
Bogue’s Compounds
1
UNIT

3. Tricalcium Aluminate –
• 4-14% by weight
• Formed within 24 hours of addition of water to cement
• Responsible for maximum amount of heat of hydration.
4. Tetracalcium Alumino ferrite-
• It is also formed within 24 hours of addition of water to cement.
• Amount of heat of hydration evolved during formation of this
compound initially is comparatively more which goes on decreasing
with time.
Bogue’s Compounds
1
UNIT

 Cement gains its strength through a chemical reaction with water. This
exothermic reaction between water and cement which liberate heat is
known as hydration. And the reaction by which cement acts as bonding
agent is called as hydration of cement. This binding action takes place in
the presence of water.
Hydration of cement
1
UNIT

 Manufacturing of Cement includes three basic operations:
 The Common two process of Manufacturing of cement are :
1. Dry process (New Method)
1. Wet process (Old Method)
1.Mixing 2.Burning 3.Grinding
Methods
Dry
Method
(New)
Wet
process
(Old)
Manufacturing of Cement
1
UNIT

Methods of Manufacturing of Cement 1
UNIT

2. Wet Process (Old Method)
Methods of Manufacturing of Cement 1
UNIT

1. Fineness
2. Standard consistency
3. Setting time
4. Soundness
5. Compressive strength
Physical Properties of OPC 1
UNIT

Testing of Cement 1
UNIT
Testing of cement is
carried out to analyze the
presence of desirable
properties in it.
Testing of
cement
Field test
1. Color test
2. Physical Test
3. Strength Test
Laboratory
Test
1.Fineness test
2. Standard
Consistency
test
3.Setting time
test
4. Strength test
5.Soundness
test

• Fineness of cement refers to the size of grains or particles of cement. Lesser
the grain size, finer the cement.
• Due to small grain size, more surface area is available for contact with water
and the reaction of hydration becomes faster, gaining of strength is more
rapid and rate of evolution of heat increases.
• Following are two methods prescribed in IS codes for testing fineness:
Methods for
testing
fineness
Sieve
Test
Air
Permeability
Method
Lab Test – 1. Fineness Test 1
UNIT

Sieve test
3. Continuously sieve the sample giving circular
and vertical motion for a period of 15
minutes. Mechanical sieving devices may
also be used.
4. Weight the residue left on the sieve.
5. This residue shall not exceed by the limits
given below:
OPC 10 gm
Rapid Hardening Cement 05 gm
1
UNIT
•Procedure
1. Weight 100gm of cement correctly and take it on a standard IS sieve
number 9, i.e. a sieve 90 micron.
2. Break down any air-set lumps in the sample with fingers.

Air Permeability test
In this method, the permeability of a cement bed for
passage of air current is related with the specific surface of
the grains of cement.
The finer the grains, the more the specific surface.
Lea and nurse permeability apparatus is used for the test ,
The diameter of the permeability cell is 2.5 cm.
Knowing the density of cement the weight of cement
required to make a cement bad of 0.475 porosity can be
calculated.
1
UNIT

Air Permeability test 1
UNIT
Lea and nurse Permeability meter

Air Permeability test 1
UNIT
The procedure of the test is given below :
1. Fill the weight of cement as calculated for making a bed of
0.475 porosity into the permeability cell.
2. Slowly pass dry air through the cement bed at a constant
velocity.
3. Read the difference in manometer limbs and note it as h1.
4. Read the difference in flow meter limbs and note it as h. It
should be between 30 to 50 cm.
4. Repeat the readings till steady state is achieved. i.e. h1/h2 is
constant

6. Specific surface is calculated by following formula.
£ = Porosity = 0.475
L = Length of cement bed (cm)
D = Density of cement in gm/cm3
C = Flow meter constant.
A = Area of c/s of cement bed (cm2)
1
UNIT

Generally values of C and K are provided by the manufacturer
for different values of porosity.
7. The specific surface should not be less than the limits given
below:
OPC :Not less than 2250 cm2/gm
Rapid hardening cement: Not less than 3250 cm2/gm
Low heat cement: Not less than 3200 cm2/gm
1
UNIT

2. Standard Consistency test
Definition:
 Standard consistency is defined as that consistency which will
permit a standard Vicat plunger to penetrate a depth of 33 to 35
mm from the top of the mould in a standard Vicat apparatus.
 The Vicat apparatus is used for three tests, namely, standard
consistency test, initial setting time test and final setting time
test by changing the attachment.
1
UNIT

Standard Consistency test 1
UNIT
Vicat apparatus

Standard Consistency test
 Procedure of standard consistency test:
1. Take about 500 gm of cement and prepare a paste with known weight of
water say about 20 - 25% of weight of cement.
2. Fill the paste in Vicat mould within 3 to 5 minutes. Level the top surface.
3. Shake the mould to expel any air bubbles.
4. Attach the plunger with the screw provided on the rod of the sliding weight.
5. Bring down the weight till plunger just touches the top surface of paste
6. Release the weight so that the plunger penetrates the paste, Measure the
penetration. This can be measured by the pointer attached to the sliding
weight and moving on the scale.
7. If the penetration is less than 33 to 35 mm from top of mould, increase the
water percentage to make a fresh paste.
1
UNIT

Standard Consistency test 1
UNIT
Procedure of standard consistency test:
7. In this manner, by making a fresh trial paste a number of times, find the
water percentage by weight, which will give the penetration of the
plunger upto 33 to 35 mm depth from top of the mould.
8. This water percentage is known consistency of the given cement and is
denoted by P.

3. Setting Times
 Setting time:
1. Initial setting Time
2. Final Setting Time
 Initial setting Time -Initial setting time is the time elapsed
between the moment when water is poured in cement to the
moment when the cement paste starts losing its plasticity.
 This test is also performed on the Vicat's apparatus, only this
time the plunger is removed and initial setting time needle is
attached in its place.
Initial setting time of cement is 30 Minutes.
1
UNIT

Setting Time-Initial setting Time
 Procedure
1. Take about 500 gm cement and mix it with
0.85P percent of water where P is the water
percentage required for standard consistency to
make a smooth paste. Start a stopwatch at the
moment when water is added to cement.
2. Fill and shake the Vicat mould with the paste
within 3 to 5 minutes after adding water.
3. Lower the initial setting time needle till it
touches the surface of the cement paste in the
mould.
1
UNIT
Initial setting Time
Needle

Setting Time-Initial setting Time
 Procedure:
4. Release the weight so that the needle penetrates the paste.
Initially, it will penetrate the complete depth, i.e. 40 mm, of the
mould.
5. Take readings after every 1 or 2 minutes and when the penetration
decreases, take reading after every 20 seconds and then after every
10 seconds, moving the mould to take reading at different place
every time.
6. Record the time on the stopwatch when the penetration is 33 to
35mm from the top surface.
7. This time is known as the initial setting time.
1
UNIT

Setting Time-Final setting Time
 Final setting Time- Final setting time is defined as the time elapsed
between the moment when water is added to cement and the moment when the
paste has completely lost its plasticity.
 Initial setting time of cement is 600Minutes (10hrs).
Procedure:
1. Remove the initial setting time needle and attach the final setting time
needle, which is very similar to the initial setting time needle, only it has a
collar with a rim attached to it. The Central needle projects 0.5 mm more
than the rim. The collar has hole known air-vent through which trapped air
in the rim escape that it does not interfere with the reading.
2. Lower the final setting time needle till it gently touches the past and
release it.
3. Observe the impression made by the attachment on the past.
1
UNIT

Setting Time-Final setting Time
4. Initially, both the rim and central needle will make the
impression. Turn the mould around and after every
few minutes, take the reading on a different place on the
surface of the paste.
5. When the impression of the rim starts a becoming faint,
take readings at very short time intervals.
6. Record the time when only central needle makes an
impression but the surrounding rim does not make
an impression at all.
7. The time elapsed between the moment when water is added to the cement
and the moment when only central needle makes an impression but the rim
fails to make impression is called the final setting time.
1
UNIT
Final setting Time
Needle

Setting Time-Final setting Time 1
UNIT
Impression of Final setting Time

4. Compressive Strength 1
UNIT
Compressive strength of cement is the most important
parameter and hence this test is one of the most
important tests.
Procedure:
1. Take 555 grams of standard sand and 185 grams of cement and
mix it in dry condition for one minute.
2. Add water of [ P/4+3.5] when ordinary sand is [P/4 +3.0] when
standard sand is used percent of combined weight of cement
and sand. Where P is the standard consistency of cement.

Compressive Strength 1
UNIT
3. Mix the three ingredients thoroughly till mixture in of uniform
color. The mixing time should be between 3 and 4 minutes. The
mould is fitted on the table of the vibrating machine
immediately. after mixing and compacted at least for two
minutes. This process should be completed within five minutes
after mixing.
4. Immediately fill the mortar thus prepared into cube moulds of
size 7.06 cm is placed on non porous base plate which is oiled
from inside. Compact the mortar by standard means.
5. Keep the mould in 90% humidity and at 27°C ± 2°C for 24
hours. Where humidity room is not available, the mould can be
kept under wet gunny bag for 24 hours.

Compressive Strength 1
UNIT
5. Remove the cubes from moulds
after 24 hours and keep
immersed under clean water till
the moment of testing.
6. Test the cubes under UTM for
compressive strength.
UTM : Universal Testing Machine

5. Soundness Test 1
UNIT
Soundness test is Performed with the le-chatelier’s apparatus.
Soundness:
It is the ability of a hardened cement paste to retain its volume
after setting without delayed destructive expansion is caused by
excessive amounts of free lime or magnesia.
Unsoundness:
If it is subjected to delayed destructive expansion of cement due
to presence of excessive amount of hard-burned free lime or
magnesia.

Soundness Test 1
UNIT
Procedure:
1. Take 100 gm of cement. This is mixed with 0.78 P times water, where P is
the water required for standard consistency and it is mixed through for
about 3 minutes.
2. The paste is filled in the split cylinder, which is covered on top and bottom
with glass plates and is kept in water at 27° to 32°C for 24 hours with a
small weight on the top glass plate for stability.
3. The distance between the pointers is measured and mould is submerged in
boiling water for 3 hours.
4. The mould is removed, allowed to cool and again the distance between the
pointers is measured again.
5. The difference between these two distances represents the expansion of
cement. This must not exceed 10 mm for OPC, Rapid hardening and low
heat cements. If it exceeds 10 mm, then the cement is said to be unsound.

Soundness Test 1
UNIT
Le-chatelier’s Apparatus-.

Soundness Test 1
UNIT
Example:
Que : Define normal consistency of cement. If normal consistency of cement is
34 % Find percentage of water required for soundness and compressive strength
test of cement.
Ans: Given- Normal consistency 34 %
1) % of water required for soundness test
= 0.78 times (Normal consistency)
= 0.78 X 34 / 100
= 0.26 %
2) % of water required for compressive strength test
P = {P/ 4} + 3.5
= {34/(4x100)} + 3.5
= 3.58 %

Grades of Cement 1
UNIT
 Different Grades of cement are specified by IS 1489- 1991.These are mainly
based on compressive strength.
1) 33 Grade cement
2) 43 Grade cement
3) 53 Grade cement
33 Grade Cement :
The cement having strength 33 grade N/mm2 after 28 days when tested is called as
33 grade cement.
Uses: Plastering, Brickwork, Tiling work
This grade has high workability and is mainly used for mortar in masonry work and
for plastering.
Properties: A) It has High Workability.
B) It used for Mortor in masonary work and for plastering

Grades of Cement 1
UNIT
43 Grade Cement :
43 grade cement.
Uses: Framed structure, RMC, PCC And RCC Work pre-cast and Prestressed
concrete, RCC Bridge.
Properties: A)Moderately Sulphate Resisting.
B) Low Chloride Content
C) It has Good Workability.
d) It gives better surface finish.
 53 Grade Cement:
53 grade cement.
Uses: RCC Structure
Properties: A)Moderately Sulphate Resisting.
B) Low Chloride Content
c) Speedy construction.

Adulteration of Cement 1
UNIT
 Adulteration means mixing very fine stone dust , fine silt or mixing powdered
fly ash or old cement to increase volume of fresh cement.
 It causes many problems and very serious consequence of adulterated cement
may result even in loss of human lives.
The adulteration of cement is done in the following ways.
1. Mixing of very fine stone-dust from quarries.
2. Mixing of fine silt.
3. Mixing of fine, powdered fly ash.
4. Mixing of lime powder or surkhi.
5. Mixing of old cement which has entirely lost its strength due to long
period of storage.

Field Test on Cement 1
UNIT
Field Test:
1. Colour test: Cement should possess uniform grey colour.
2. Physical property test:
 Should feel smooth when rubbed in between fingers.
 It should not feel oily when touched.
 Cement should sink in water and should not float over the surface.
 Sample should be free from presence of any lumps which are formed due to
absorption of moisture.
3. Strength test:
 Prepare a block of cement to be tested of size
25 X 25 X 200 Cubic mm.
 Immerse in water for 7 days.
 Now remove the mould and subject it to point
load of 340N by placing it over supports 150mm
apart.
 Sample should show no sign of failure under the application of this load.

Storing of cement on site 1
UNIT
Storing of cement:
The cement should be stored in such a way that
It cannot expose to the Atmosphere. So air
tight bags are used to pack the cement.
The absorption of moisture from atmosphere
will also depends up on the quality of cement.
Precautions:
1. Cement should be stored in a special water-tight shed with a dry and damp
proof door, waterproof walls and leak-proof roof.
2. The stacks of cement bags should be placed at a distance of at least 30 cm
from walls.

Storing of cement on site 1
UNIT
 Precautions:
3. A stack should contain maximum 15 bags.
4. Width of a stack should not exceed 3 m.
5. Bags should be stacked on a raised platform, with sufficient air for
movement between rows of stacks.
6. Bags should be stored in such a way that bags received first should be
used first.

Effect of Storage of cement on
Properties
1
UNIT
Due to long storage, cement loses its strength, becomes lumpy and due to its
loss of capacity for hydration, becomes unusable.
It is advisable to use cement within 3 months at the maximum.
The strength at different time periods as follows:
Cement Reduction in strength
Fresh NIL
After 3 months 15%
After 6 months 25%
After 1 year 40%
After 2 year 52%

Types of Cement 1
UNIT
 Types Of Cement:
1. Rapid Hardening Cement
2. Low Heat Cement
3. Pozzolana Portland Cement
4. Sulphate Resisting Cement
5. Blast Furnace Slag Cement
6. White Cement
7. Oil Well Cement
8. Hydrophobic Cement

Types of Cement 1
UNIT
1. Rapid Hardening Cement:
• Higher Rate Of Development Of Strength.
• Must Not Be Confused With Quick Setting Cement.
• Strength Of RHC At The Age Of 3days Is Same As That Of OPC At 7
Days.
• After 90days, strength of RHC and OPC is almost same.
• Produced by fine grinding of clinkers, increasing proportion of C3S and
reducing C2S.
• Used in pre fabricated construction work, cold weather concreting where
framework is used for speedy construction.

Types of Cement 1
UNIT
1. Rapid Hardening Cement:
The physical requirements of Rapid Hardening
Cement are:
1. Fineness -3250 cm2/gm minimum.
2. Le-chatelier soundness - 10 mm maximum.
3. Initial setting time - 30 minutes minimum.
4. Final setting time - 600 minutes maximum.
5. One day compressive strength - 16 MPA.
6. Three days compressive strength - 27 MPA.

Difference between OPC & RHC 1
UNIT
Sr.
No.
Ordinary Portland Cement
(OPC)
Rapidly Hardening Cement
(RHC)
1. It develops strength It
within 7 days.
It develops strength
Within 3 day.
2. It is suitable for mass
concreting work.
It is not suitable mass
concreting work.
3. Normal % regard for In this
OPC is used.
In this cement % of C3S
increased and C2S is reduced.
4. It is not suitable in cold Weather
Concreting.
It is suitable in cold Weather
Concreting.
5. As early setting is not possible
formwork can not be removed
earlier
Due to early setting formwark can
be remove earlier and thus reduce
cost of formwork.

Types of Cement 1
UNIT
2. Low Heat Cement:
• Produced by reducing proportion of C3S & C3A and increasing the
proportion of C2S.
• This cement shows slow rate of development of strength
• Used where mass concreting such as dams , nuclear power plants etc.
The physical properties of Low Heat Cement are
1. Fineness - 3200 cm2/gm.
2. Soundness not more than - 10 mm.
3. Initial setting time - 60 minutes.
4. Final setting time - 600 minutes.
6. Compressive strength -
3 days - 10 MPA
7 days- 16 MPA
28 days- 35 MPA
• The new IS code for low heat cement is IS12600-1989.

Types of Cement 1
UNIT
• Pozzolana is a very old construction
material which was used even in
Roman times.
• The pozzolana constituent must be
within 10 to 25 percent. The
mixing of pozzolana component and
OPC should be very thorough.
• The fineness through 90 micron sieve should not be more than 5%
residue.
• Portland pozzolana cement can be called a type of low heat cement
as it produces less heat of hydration.

The physical properties of Pozzolana Portland Cement are:
1. Fineness -3000 cm2/gm.
2. Soundness -10 mm
3. Initial setting time - 30 minutes.
4. Final setting time -600 minutes.
5. Compressive strength.
3 days - 16 MPA
7 days - 22 MPA
28 days - 33 MPA
• The new IS code for PPC is IS 1489-1991-part I.
Types of Cement 1
UNIT

Types of Cement 1
UNIT
4. Sulphate Resisting Cement:
• OPC is highly susceptible to attack of sulphates.
• Its manufactured by reducing proportion of C3A and C3AF such that C3A is not
greater than 5% and 2C3A + C4AF should not be greater than 25%.
• Used in foundation work , sewage treatment work, marine structures and
construction of pipes in marshy areas.
The physical properties of Sulphate Resisting Cement are:
1. Fineness-2250 cm2/gm.
2. Soundness- 10 mm
3. Initial setting time - 30 minutes
4. Final setting time-600 minutes.
3 days-16 MPA
7 days-22 MPA
28 days-33 MPA
• The latest IS code for SRC is IS 12330-1988.

Types of Cement 1
UNIT
5. Blast Furnace Slag Cement:
• Slag from a blast furnace is actually a waste product But it can be
profitably used for manufacture of cement..
• This cement is similar to OPC and only gains the full strength a bit later.
This cement is quite economical compared to OPC.
• This cement is resistant to sulphate attack and other chemical attacks.
• Field application: This cement is mainly used in marine Construction.
• The physical properties of Blast Furness Slag cement are:
1. Fineness-2250 cm2/gm.
2. Soundness- 10 mm
3. Initial setting time -30 minutes minimum.
4. Final setting time - 600 minutes maximum.
3 days - 16 MPA
7 days - 22 MPA
28 days - 33 MPA

Types of Cement 1
UNIT
6. White cement:
• ACC first manufactured white cement in India under the trade name of
"silvercrete" now-a-days, Birla cement has manufactured "Birla white“.
• The manufacture of white Portland cement requires suitable raw materials and
special care against contamination during production.
• Field application: White cement is used in decorative construction and in high-
class tiling work so that the joints are not visible.
• White cement can be used as a base for colored cement,
But it is costly. With grey cement only red or brown
cement can be produced.

Types of Cement 1
UNIT
6. White cement:
 Physical properties of typical white cement are
1. Degree of whiteness: % IS code 70 % min 88 % and above max.
2. Fineness- 2500 cm2/gm.
3. Initial setting time-300 minutes
4. Final setting time - 600 minutes
5.Compressive strength.
3 days 14.4 MPA minimum and 45 MPA maximum
7 days 19.8 MPA to 55 MPA maximum
28 days 29.7 MPA to 67 MPA maximum

Types of Cement 1
UNIT
7. Oil Well Cement
• It is chiefly used for cementing oil wells. Cement is manufactured by
adjusting the proportion of iron oxide so that all the alumina is converted to
C4AF. By doing so, the proportion the compound C2A formed is very small
and thus the setting time of cement is increased.
• Use-oil well cement is used for cementing the oil wells.
This is done by filling the space between the steel lining
tube and well of the well and by grouting the porous
strata to prevent water or gas form gaining access to the
oil bearing strata.

Types of Cement 1
UNIT
8. Hydrophobic Cement
 This cement produced due liability of OPC deteriorate and from lumps
absorbing moisture atmosphere during the period of its storage.
 It has been found, that if certain water repelling materials are ground with
cement clinker during manufacturing these substances form a water
repellent film round each cement grain and prevent the possibility of water
absorption from atmosphere avoiding its detoriation.
 This film breaks down due to abrasion with the
aggregate when the concrete is mixed and normal
hydration takes place. Then this cement is
called a hydrophobic cement.

1
UNIT
THANK YOU !!!

Unit 1 cement

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