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The word cement has come from the roman word ‘OPUS CAEMENTICIUM
An adhesive substance of all kinds, but, in a narrower sense, the binding materials used in building and civil engineering construction.
What Is CEMENT?
History of CementBefore the 18th century• Cement made with lime, sand,
and gravel was used.• Examples: Dome of Pantheon
of Rome, Baths of Caracalla
18th, 19th, and 20th centuries• Portland cement patented by
Joseph Aspdin • Blend of Rosendale and
synthetic cement 21st century and future…• OPC most common. Base of
concrete, mortar, grout• Green Cement made by recycled
coal, ash, bio-mass, mine tailings, etc.
PhysicalStrength to masonryExcellent binding
material Easily workableStiffens earlyPossesses good plasticityOffers good resistance to
the moistureFineness: Soundness
Alumia: Iron oxide ≥ 0.66
0.66≤Lime saturation factor ≤1.02
Sulphur content ≤ 2.75 %
Wt. of insoluble residue ≤ 1.5%
Properties of cement
Chemical
COMPOSITIONIt is quite important
to maintain the composition of cement because all the functions of every type of cement depends on individual quantity of every component.
LIME 63%
SILICA 22%
ALUMINA 06%
IRON OXIDE 3%
GYPSUM 1-4
%
FUNCTIONS OF CEMENT INGREDIENTS
•Controls strength and soundness
LIME (CaO)
•Gives strength, excess quantity causes slow setting
SILICA(SiO2 )
•Quick setting, excess lowers strength
Alumina (Al2O3)
•Imparts color, helps in fusion of ingredients
IRON OXIDE(Fe2O3)
•Color and hardness, excess causes cracking
Magnesium Oxide (MgO)
•It makes the cement sound.
Sulphur Trioxide (SO3)
FUNCTIONS OF CEMENT INGREDIENTS
Demerits Merits
resistant to wind, water, rodents, and insects
Stands high temp. Fire safe.
molded in desired shape
Long Life
low ductility
susceptible to cracking
low tensile strength
WhiteUsed in making
pre cast wall
Pozzolana
Used in marine structur
es, sewage works, dams
Oil Wellused in constructing or fixing
oil wells.
ClinkerUsed in construction of complex
es, houses, bridges
Rapid Hardeni
ngFiner than
OPC so casting is easy
Sulphate
Resisting
PortlandProtects
the structure from sulphat
e attacks
TYPES OF CEMENT
Uses of Cement
concrete,Masonry, pointing, plastering
Foundations,
foothpaths
For filling cracks
Joints for drains , pipes
Engineering structures
like bridges, culverts ,
dams
Laying floors , roofs,
constructing lintels, beams , weather sheds
To manufactur
e bricks
Limestone is brought from
mines
Limestone is crushed
Some additives are added at this
stage
Mixture is grinded to form homogeneous
mixture
Formation of clinker at high
temperature
Suitable are additives are added and again grinded
This yields
cement
Manufacturing of cement
BURNINGHeating in a kiln
Produces “çlinker’
Addition of gypsum
PREPARATION OF RAW MATERIALS
PROCESSING TO CONTROL THE COMPOSITION AND PROPERTIES OF THE CEMENT
ACQUISITION OF RAW MATERIAL
CALCIUM SOURCE CONTROLS LOCATION OF PLANTSSILICA USUALLY SHIPPED TO CEMENT PLANT
CEMENT Production
Regulates set and clinker + gypsum=cement
Setting and harderning of cement
Setting- is used to describe the stiffening of the cement paste. It refers to changes of cement paste from a fluid to rigid state. Setting differs from Hardening of cement.
Hardening –it refers to the gain of strength of a set cement paste, although during setting the cement paste acquires some strength.
Initial setting time indicates the beginning of the setting process when the cement paste starts losing its plasticity.
Final setting time is the time elapsed between the moment water is added to the cement and the time when the cement completely lost its plasticity and can resist certain definite pressure.
It includes two processes initial set and final set stages
SITE FOR CEMENT FACTORY• SHOULD BE FAVOURABLE AND
SUITABLE FOR THE SETTING AND HARDENING
CLIMATE• SHOULD BE EASILY AVAILABLE AND
ECONOMICALLABOUR• SHOULD BE NEAR . WILL DECREASE
COST OF TRANSPORT MARKET• RATES SHOULD BE ECONOMICAL.
CUTS MINIMAL.POWER• EASILY AVAILABLE. CONTINUOUSLY
AVAILABLE AROUND SITE.RAW
MATERIALS• EASILY AVIALBLE FOR RAW
MATERIALS AND FINISHED MATERIALS.
TRANSPORT
INDIAN CEMENT INDUSTRYThe Indian cement
industry is the 2nd largest market after China accounting for about 8% of the total global production.
Housing sector is the biggest demand driver of cement(67%) followed by infrastructure (13%), commercial construction (11%) and industrial construction (9%).
Andhra Pradesh is the largest producer of cement in India followed by Rajasthan and Tamil Nadu.
SATNA, cement city, in MP, is in the limestone belts of India. As a result, it contributes around 8%–9% of India's total cement production.
India is producing different varieties of cement like ordinary Portland cement, Oil well cement, sulphate resisting cement, white cement etc. Production of these verities conform to BIS standards.
INDIAN CEMENT INDUSTRY
FUTURE ALTERNATIVES TO CEMENTQuantity of trash is Increasing in this world day by day which has ignited the architects to find new ideas such as :
• Alok shetty’s concept of recycling tin cans, plastic bottles, etc and laying them with very less quantity of cement.
• GREEN CEMENT• REASEARCH by Peter
Trimble who proposed a bacterium based design combined with sand producing 70% much stronger cement.
•UNIFORM•GREENISH GRAY•GIVES INDICATION OF EXCESS LIME/CLAYCOLOR
•FEEL SMOOTH. IF ROUGH; ADULTERATION OF SAND•HAND IN BAG SHOULD FEEL COOL NOT WARM•EARTHY SMELL IF TOO MUCH CLAY OR SILT ADULTERANT•SHOULD BE FREE FROM ANY HARD LUMPS
PHYSICAL PROPERTIES
• Thick paste of cement made on thick glass and kept underwater for 1 day. Should set and not crack!
STRENGTH
FIELD TESTS and MARKET SURVEY
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