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									CEMENT and
CONCRETE
  Alcaraz, Marissa
     Ang, Jean
                  CEMENT
 Substance that combines solid bodies by hardening.
 Includes organic polymer-based cements
 Most popular type of cements
   Blended
   Hydraulics
   Portland
NATURE OF PORTLAND
     CEMENT
                   Portland Cement
 Abundant use in construction
 Joseph Aspdin of Leeds
 Mixture of:
      Silicates
      Aluminates
      Ferro – Alluminates of lime
      Silica
      Iron oxide
      Alumina

 Mixture is burned to incipient vitrification
 Resulting clinker is grinded to a fine powder
 Gypsum is added
       TYPES OF PORTLAND
            CEMENT
   Type I – general purposes
   Type II – structures in water or soil
   Type III – high strength in small amount of time
   Type IV – moderation of heat in which hydration is needed
   Type V – ability to resist chemical effects by soil and water
   Type IA, IIA, IIIA – carries air substance
   White Portland Cement – small or no amount of manganese
    iron
PROPERTIES OF CEMENT
CHEMICAL COMPOSITION
 CHEMICAL COMPOSITION
 Gypsum 3.5%
 Tetracalcium Aluminoferrite 8%
 Tricalcium Aluminate 12%
 Dicalcium Silicate 25%
 Tricalcium Silicate 50%
 Other 1.5%
     PHYSICAL PROPERTIES
 FINENESS
   The finer particles are the ones that mainly affect the early
    strength of the cement while the larger particles controls the
    strength after that particular time.



 SETTING TIME
     time that it takes for the cement paste to change form
      from fluid to a rigid state.
  PHYSICAL PROPERTIES
 SOUNDNESS
  ability of the hardened cement paste to preserve its
   volume after setting without delayed destructive
   expansion


 STRENGTH
  Compressive
  Tensile
  Flexure
   PHYSICAL PROPERTIES
 HEAT OF HYDRATION
   it is the heat produced when the water and Portland
    cement react


 LOSS ON IGNITION
   weight loss of the sample due to heating
   high loss can mean that pre-hydration and carbonation
    occurred that may be rooted from improper and
    prolonged storage
APPLICATIONS
           APPLICATIONS ON
             STRUCTURES
 Concrete
 Walls
 Buildings
 Bridges
 Floors
 Reservoirs
  MILITARY APPLICATIONS
 Ships
 Tanks
 Bunkers
MANUFACTURING
         MANUFACTURING
 Quarrying
 Raw Material Preparation
 Clinkering
 Cement Milling
               QUARRYING
 Rock or mineral extraction
 Gives main strength of the cement
 Provides cement with grey color
           RAW MATERIAL
           PREPARATION
 Dry Process
 Wet Process
 Crushing and Grinding machines
 Crushing and Grinding Machines
 Jaw Crushers – swinging jaw operates against a fixed
  jaw
          Gyratory Machines
 More suitable for gypsum
                Roll Crushers
 Single roll, double roll, corrugated surface, high speed
  roll, slow speed gear driven roll
      Hammer Type Crushers
 Will accept whatever pieces that will enter
              Cone Crushers
 reduces the oversize material to the size
  predetermined by the initial setting without reducing
  other pieces with that size
                Grinding Mills
 Singe unit, two mill type
               CLINKERING
 Used to take the form of Portland Cement
 Processes
   Drying - Pre heater
   Heating – Kiln
   Cooling – Large Cooler
           CEMENT MILLING
 Mixed with gypsum
 Grinded for another 30 minutes using large tube mills
 Cement will flow from inlet to outlet using rotating
  chambers
LATEST DEVELOPMENTS
                Soil - Cement
 Compacted combination of Soil, Portland cement, and
  water

 Soil particles are more held together
                Soil - Cement
 Center Modified Soils
   Soil is combined with only a small amount of Portland
    cement
   Used to modify unwanted properties of soil problems
                Soil - Cement
 Full – Depth Reclamation with Cement
   Repairs broken or old asphalt pavements by reusing the
     base to provide more stabilized cement for new roads
   Saves money and natural
  resources because it reuses
  and recycles original base materials
   Simple and Fast –
  can be finished in one day
       Cement – Treated Base
 Mixture of aggregate material, measured Portland
  cement, and water that solidifies after compaction and
  curing to form a strong paving material
 Maximum compaction
 Most commonly used in
     Highways
     Roads
     Streets
     Parking Areas
     Airports
CONCRETE
                   Concrete
 A composite construction material
 Known by Ancient Romans and widely used in the
  Roman Empire
Nature of Concrete
            Nature of Concrete
 It is made up of a binder and a filler wherein the binder
  (cement paste) "glues" the filler together to form a
  synthetic conglomerate. The constituents used for the
  binder are cement and water, while the filler can be fine
  or coarse aggregate.

 The binder controls the properties of the concrete
 The cement commonly used for the binder is Portland
  cement.
                    Concrete
 Some common and main types of concrete are:
   Normal concrete - The concrete in which common
    ingredients i.e. aggregate, water, cement are used is
    known as normal concrete.
   High Strength Concrete - High strength concrete is
    made by lowering the water cement (W/C) ratio to 0.35 or
    lower.
   High Performance Concrete - The admixtures are 20-
    25% fly ash of partial replacement of cement and rest
    70% is Ordinary Portland Cement.
                  Concrete
 Air Entrained Concrete - It is used where the concrete is
  vulnerable to freezing and thawing action.
 Light Weight Concrete - The concrete which has
  substantially lower mass per unit volume than the
  concrete made of ordinary ingredients.
 Self Compacting Concrete - The concrete is
  compacted due to its own weight. Similar to high-
  performance but workability is increased.
 Shotcrete - It can be impacted onto any type or shape of
  surface, including vertical or overhead areas.
                   Concrete
 Pervious Concrete – It contains a network of holes or
  voids, to allow air or water to move through the concrete.
 Roller Compacted Concrete - It is a low-cement-
  content stiff concrete placed using techniques borrowed
  from earthmoving and paving work.
Properties
              Physical Properties
• Strength of Concrete
  The compressive strength of concrete is very high, but its tensile strength
  is relatively low. Since concrete must resist a great deal of stretching,
  bending, or twisting, it must be reinforced with steel.

• Durability of Concrete
  The durability of concrete, or its strength, is determined largely by the
  water-cement ratio. This durability gives concrete the ability to resist
  deterioration caused by ‘wear and tear’ and exposure to the elements. The
  character, size, and grading of the aggregate also have important effects
  on both strength and durability.

  However, the character, size, and grading of the aggregate also have
  important effects on both strength and durability.
              Physical Properties
• Water tightness of Concrete
  In order to keep the concrete as watertight as possible, the amount of
  water used must be minimized to achieve the necessary degree of
  workability.

• Concrete is strong and fireproof.

• Concrete that is subject to wear, such as floor slabs and pavements, must
  be capable of resisting abrasion.
         Chemical Properties
 (cement + water) + aggregate = concrete
 Most concrete is made with a water to cement mass
  ratio ranging from 0.35 to 0.6

 Aggregate is the solid particles that are bound together
  by the cement paste to create the synthetic rock known
  as concrete. (ex. Gravel, limestone, granite)
         Chemical Properties
 Other materials may be incorporated into concrete to
  create specific and different characteristics.

 These additives are called admixtures. Admixtures are
  used to: alter the fluidity of the cement paste; increase
  or decrease the setting time; increase strength (both
  bending and compression); or to extend the life of a
  structure.
Application
              Applications on
              Infrastructures
 Architectural structures
 Pavements
 Bridges/Overpass
 Motorways/Roads
 Runways
 Boats
 Dams
 Pools/Reservoir
            Building Support
 Fences
 Poles
 Pipes
 Foundation
 Brick/block walls
 Parking Structure
 Footings for gates
Manufacturing
   Manufacturing of Concrete
 Prepare Portland cement
   The limestone, silica, and alumina that make up Portland
    cement are dry ground into a very fine powder.
   The clinker is then cooled and ground to a fine powder in a tube
    or ball mill.

 Mixing
   The cement is then mixed with the other ingredients:
    aggregates (sand, gravel, or crushed stone), admixtures, fibers,
    and water.
   Fibers, if desired, can be added by a variety of methods
    including direct spraying, premixing, impregnating, or hand
    laying-up. Silica fume is often used as a dispersing or
    densifying agent.
   Manufacturing of Concrete
 Transfer to work site
   Once the concrete mixture is ready, it is transported to the
     work site.

 Placing and compacting
   Once at the site, the concrete must be placed and
     compacted. These two operations are performed almost
     simultaneously.

 Curing
   Once it is placed and compacted, the concrete must
     cured before it is finished to make sure that it doesn't dry
     too quickly.
Latest Development
        Latest Developments

 Environment-friendly Concrete
   London-based Novacem, claim to have developed a new
    form of concrete that effectively absorbs large amounts of
    carbon dioxide as it hardens.
         Latest Developments
 Glass Reinforced Concrete
   Introduced into the field in the 80s, it is a solution deriving
    from pre-stressed concrete, where ribbed steel wires are
    stretched through sections of concrete during the setting
    process to give added torsional strength.
   It replaces steel inserts with alkali resistant glass fibers.
                 References
 Avsar, H. (2006). CONTROL, OPTIMIZATION AND
  MONITORING OF PORTLAND CEMENT (PC 42.5)
  QUALITY.
 Bye, G. C. (1999). Portland Cement. London: Thomas
  Telford Publishing.
 Davis, C. (1948). Portland Cement. London: Concrete
  Publications Limited.
 Wansbrough, H. (1989). The Manufacture of Portland
  Cement. The Cement and Concrete Association of New
  Zealand .
                  References
 http://matse1.matse.illinois.edu/concrete/prin.html
 basementleakrepairs.com/nature_of_concrete.htm
 http://www.madehow.com/Volume-1/Concrete.html#b
 http://www.sustainablebuild.co.uk/environmentally-
  friendly-concrete.html
 http://www.xymara.com/index/designerscorner/Spotligh
  t/16140/concrete.htm
 http://www.aboutcivil.com/types-of-concrete.html#hi
END OF PRESENTATION

								
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