PPT ON CONSTITUENTS AND APPLICATIONS IN CONCRETE

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1.CONSTITUENTS AND APPLICATIONS IN CONCRETE

2.CONSTITUENTS OF CONCRETE
Cement
Water
Sand (Fine Aggregate)
Coarse Aggregate
Chemical Admixtures
Mineral Admixtures

3.CEMENTS
OPC(33 grade,43 grade,53 grade)

PPC (33 grade)(15-35% flyash)

PSC (33 grade)(25-70% slag)

4.CEMENT STRENGTH
43 grade cement
     3-Day strength-23MPa,Min.
    7-Day  strength-33 MPa,Min.
   28-DAY strength-43 MPa,Min.

   53 grade cement
    3-Day strength-27MPa,Min.
    7-Day strength-37MPa,Min.
   28-Day strength-53MPa,Min.  

5.IMPORTANT PROPERTIES OF CEMENT
Fineness(Blaine’s ),cm2/gm,Setting time
Compressive strength
Heat of hydration, Calories/gm or KJ/Kg
           1calory = 4.187 Joules
Alkalis(Na2O, K2O)
   Na2O Equiv.(%)=Na2O(%) +0.658K2O(%)
 Low Alkali OPC:<0.6%alkali as Na2O Equiv.

6.Typical Data On Heat of Hydration of Cements

7.TYPICAL DATA ON ALKALI OF OPC

8.LOSS OF STRENGTH OF CEMENT WITH TIME

9.TYPICAL PHYSICAL TEST RESULTS OF OPC AND PSC

10.WATER

11.TYPICAL CHEMICAL TEST RESULTS(%) 0F OPC,SLAG &PSC

12.FLYASH (GOOD QUALITY)

13.So,when we use PPC or flyash in
      concrete,pozzolanic reaction takes
      place between flyash and the lime
     [ Ca(OH)2] liberated due to the hydration
       of OPC.
     Similar pozzolanic reaction takes place
       when we use slag(g.g.b.s) or PSC in    
        concrete.

14.BENEFICIAL EFFECT OF FLYASH AND G.G.B.S
Fresh concrete has improved workability.
The heat development is slower,and so
     the peak temperature inside the  
     concrete is lower.
The result is a denser microstructure
    of the hydrated cement paste and
    hence,improvement in the long-term
    strength & enhanced durability of concrete.

15.TYPICAL TEMPERATURE- RISE OF CONCRETE WITH PSC

16.APPLICATIONS OF CEMENTS

17.IN AGGRESSIVE ENVIRONMENTS
For aggressive environments,we prefer
   blended cements( PPC or PSC).
When there is SO3 in soil & ground water,
    Low C3A (<5%) sulphate-resisting
       cement should be used.
When both SO3 & Cl are there :OPC(with
  5-8% C3A or PSC(with>50% slag) is
   required to be used.

18. Low alkali(<0.6% alkali as Na2O Equiv.)OPC is     to be used in concrete dams & in other
   Hydraulic structures(e.g.in Tunnel linings,
    Power Houses,Spillways etc.),because in
   Himalayan regions,aggregates may be reactive.
   
      Use of flyash(at least 20%) or slag(at least
        50%) along with low alkali OPC will
        be advantageous,in such cases.

19.MASS CONCRETE STRUCTURES
In mass concrete structures (massive
  structures: size >1m),OPC(33grade) will
  be preferred for low grade (say M15)
   concrete (eg.concrete dam),because of
   low heat of hydration in this cement.
   PPC or PSC can also be used.
Because of low heat of hydration,the
   temperature rise inside the concrete
    will be less.

20.TYPICAL APPLICATIONS
      Use of 43 grade OPC:
   In RMC plants( 43grade OPC+ Flyash).
  In concrete roads(M40 grade of concrete
   for National Highways, M30 grade of
    concrete for Rural roads).
   Use of 53 grade OPC:
     In high strength concrete(M50,M60,M70
     and M80)

21.USE OF 53     GRADE OPC
In prestressed concrete railway
     sleepers(M50 grade concrete).
In Delhi Metro precast segments(M50
       grade concrete), bridge piers(M60
       grade of concrete, bridge pedestals
     (M70 grade of concrete) over river Yamuna.
  Terhi dam Spillway(M60 grade of concrete).
Kol dam Spillway( M80  grade  of concrete).

22.USE OF (OPC + FLYASH)
In Ready Mixed Concrete Plants.
Delhi Metro Underground Bottom Slabs
   (M35 grade concrete)(30% flyash+OPC).
 In Ropar (Punjab ) concrete roads
     (M40 grade concrete using 50% flyash).

23.USE OF SLAG OR PSC
In concrete Pile cap in Durgapur steel
   plant modernisation project(M40 grade
    concrete).
In Bandra(Mumbai) sewage disposal
    pipe line(OPC 53-grade+70% slag used)(M45 grade).
      In marine jetty at Ennore(Tamil Nadu)(M35 &M40).
In M40 grade Petronet concrete piles at
   Dahej(Gujarat).
In concrete dam(100m high) at Koteshwar
    (in Uttarakhand)( PSC with 55% slag was used).

24.In a cable stayed bridge at sea(Norway)         (PSC was used for M70 grade concrete)
In the twin towers at Kualalumpur
    (OPC+PFA)was used for M80 grade
        concrete).
In Euro tunnel (M30 grade concrete),
    ( OPC + slag +flyash) were used.