property of construction material, bricks, stone

1. SUNDARRAJAN P
LECTURER/ CIVIL

2. ✓ All building composed of different types of material
✓ It is essential for builder, engineer, contractor or
architect to known the materials thoroughly
✓ This helps in achieving economy in cost
✓ Correct material result better strength, appearance
and function
✓ 30 to50 % cost goes under material buying

3. UNIT I
 Introduction
 Rocks and stones
 Bricks
 Lime and pozzolanas
 Cement
 Water
 Glass
 Ceramic products

4.  1.1 INTRODUCTION
 Physical properties of materials ( Definitions only )
 Density,
 Bulk density,
 Specific gravity,
 porosity,
 water absorption,
 permeability,
 chemical resistance,
 fire resistance,
 weathering resistance,
 thermal conductivity,
 Durability.

5. Density
 Ratio of mass of an
object to its unit volume
 Ρ = M/v (kg/cm3)
 M= mass
 V= volume (exclude
voids)
Bulk density
 Ratio of weight of an
object to its unit volume
 γ = w/v (kg/cm3)
 w= weight
 V= volume (include
voids)

6. Specific gravity
 Ratio of density of an
object to density of
water
 G= γs/γw (no unit)
 γs = density of object
 γw = density of water
Porosity
 Ratio of volume of voids
to the total volume of
material
 n = Vv/v x100
 Vv= volume of voids
 V= volume

7. Water absorption
 Property of material
which absorbs water
from surroundings
 Eg. Stone, brick
important
Permeability
 Property of materials
which permits seepage
of water into it
 Eg. Important in soil

8. Fire resistant
 Ability of material to
resist action of high
temperature without
losing its property
 Inflammable – petrol,
diesel
 Non inflammable-
wood
Chemical resistant
 Ability of material to
resist action of
chemicals

9. Weathering resistance
 Ability of material to
withstand alternate wet
and dry condition
without losing its
property
Thermal conductivity
 Property of material to
absorb heat
Durability
 Property of material to
withstand combined
action of atmosphere
and other factors

10. 1.2 ROCKS AND STONES
 Rocks – Classification of Rocks – Geological, Physical
and Chemical classification
 Uses of stones
 Requirements of a good building stone –
 Natural and Artificial stones for flooring Examples

11. Rocks and stone intro
 Very early time known construction materials
 Used in all over the world
 Pyramid , taj mahal, ancient temples, red fort etc..,

12. Classification of rocks
❖ Geological classification
• Igneous rocks
• Sedimentary rocks
• Metamorphic rocks
❖ Physical classification
• Stratified rocks
• Unstratified rocks
• Foliated rocks
❖ Chemical classification
• Siliceous rocks
• Argillaceous rocks
• Calcareous rocks

13. Igneous rock
 Rock formed by cooling of hot magma from
volcanoes
 Eg. Granite

14. Sedimentary rock
 Rocks formed by deposition of weathering product of
pre existing rock
 Eg. Lime stone

15. Metamorphic rock
 Formed by change in characteristics of pre existing
rock due to pressure and temperature
 Eg. Marble

16. Sedimentary rocks

17. Stratified rock
 Rocks easily cut along its edges
 Eg. Slate

18. Unstratified rock
 Rocks can’t easily cut along edges
 Compact granular structure
 Eg. Granite

19. Foliated rocks
 This rock has tendency to split in definite direction
 Eg. marble

20. Siliceous rock
 Silica predominates
 Hard and durable
 Eg. granite

21. Argillaceous rock
 Clay predominates
 Soft or compact
 Eg. slate

22. Calcareous rock
 Calcium carbonate predominates
 Eg. marble

23. Uses of stones
Construction of wall, foundation, roof, floor,
column
Face works
Paving stones for foot paths and roads
Basic material for concrete cement
Miscellaneous for ballast in railway, dam,
pier, abutment, retaining wall

24. Requirements of good
building stone:
✓ Appearance and color
✓ Crushing strength
✓ Durability
✓ Fracture
✓ Hardness
✓ Percentage wear
✓ Resistance of fire
✓ Specific gravity
✓ Texture
✓ Water absorption
✓ Seasoning
✓ Toughness index

25. Appearance
 Uniform colour and free
from holes and clay
Crushing strength
 Good building stone
should have greater
than 1000 kg/cm2
Durability
 Good building stone
should be durable in all
atmospheric and
weathering condition

26. Fracture
 Good building stone
should have sharp,
even and clear fracture
Hardness
 >17 = road works
 14 – 17 = building works
 <14 = poor hardness
Percentage wear
 Good building stone
should have less than
3%

27. Fire resistance
 Good building stone
should be fire proof
Specific gravity
 Good building stone
should have greater
than 2.7
Texture
 Good building stone
should have fine
crystalline structure

28. Water absorption
 Good building stone
should have less than
0.5% when immersed in
water for 24 hrs
Seasoning
 Period of 6 to 12 months
Toughness index
 <13 = poor
 13 -19 = moderate
 >19 = high

30. Granite:
✓ It is a igneous rock.
✓ Hard & durable.
✓ High resistance to weathering.
✓ Texture varies with quality.
✓ Specific gravity 2.3 to 2.5
✓Used for road metal, railway ballast &
aggregate

31. Kota stone
It is widely used due to durability and better
appearance.
It is non slippery, stain removable, non porous, shiny
finish.
Low cost

32. Cuddapah stone
It is a black colored lime stone.
Resembles like granite but less than quality and cost
It is used for flooring, paving etc…

33. Shahabad stone
Calcium carbonate is a major
constituent.
It is widely used in interior flooring and for
decorative purpose.
In dry places it is cooler than concrete.
Prefect raw material for cement

34. Sand stone
It is a sedimentary rock.
Easy to craving
Made light granular materials
Specific gravity is 2.65-2.95.
Used for ashlar works.

35. Marble
It is a metamorphic rock.
Hard and polished easily.
Its specific gravity is 2.7
Used in floors and stairs

36. Artificial stones
❖ It is also known as reconstructed stones.
❖ It is used in place of where natural stone is not
available
Manufacturing:
 Crushed the natural aggregate in to less than 6mm
 Remove the dust
 1:1.5:1.5 (cement : 3-6mm :<3mm)
 Suitable pigments is added
 Then water is added and mixed thoroughly
 Then cast into mould and cured
 If required polish is done

37. Cement concrete stones
It is a mixture of cement, water, coarse
aggregate and fine aggregate.
It may be cast in situ or pre cast.
Nowadays used most commonly
Reinforcement is added then it is called
R.C.C

38. Mosaic tiles
Pre cast concrete tiles with marble chips on top.

39. Terrazzo
It is a mixture of marble chips, pigments and cement.

40. Bricks
Small rectangular shaped clay generally burned or
dried one used in construction process
Brick earth:
Suitable soil for making brick
Composition of good brick earth:
 S – silica – 60-50%
 A - alumina – 20-30%
 L – lime - 10%
 I – iron oxide – 5-6 %
 M – magnesia – 1%

41. Silica:
It imparts hardness and
durability
Reduces shrinkage
Prevents cracking
Alumina:
✓It imparts plasticity to earth.

42. Lime:
❖ Used as burning flux
❖ It prevents shrinkage.
Oxide of Iron:
❖ It imparts red color to bricks.
Magnesia:
It decrease the shrinkage.

43. Manufacture of bricks
1. Preparation of clay
2. Moulding
3. Drying
4. Burning

44. Preparation of clay:
 Unsoiling:
unwanted things to be removed from the
excavated soil (roots, dust etc.,)
Digging:
Clay is spread out 60cm to 160cm heaps.
Blending:
then suitable ingredients is added then mixed
thoroughly
Tempering:
Pressed under the feet of men or cattle.
if quantity is large pug mill is used

45. Pug mill:
 cone shaped cylinder
 Height – 2m
 For tempering knifes are attached to vertical shat at
an angle of 45˚
 Operated by machine or cattle
 Bottom has opening for collecting the tempered soil

46. Moulding
 hand moulding:
 Machine moulding.
Hand moulding
✓ Rectangular box made of timber or steel with bottom
and top portion opened
✓ To avoid sticking immersed in water
✓ Two types
✓ Ground moulding
✓ Table moulding

47. Ground moulding
 Flatten the ground and layer of sand is sprayed
 Then clay is filled in mould for moulding
 Hard to insert frog
 Hard faces of brick

48. Table moulding:
Moulding is done on
table of size 2 x 1m

49. Machine moulding
 Huge quantity of bricks are made
 Types
 Plastic clay machine
 Dry clay machine
Plastic clay machine
 It has opening of brick width and length
 When plastic clay comes over this machine it is cut by
wires fitted on frames
 It is also called wire cut bricks

50. Plastic clay machines:

51. Dry clay machines:
 It is moulded by pressing the plastic clay
 Hard and perfect shape
 Its weight is higher than other type of
bricks

52. Drying
 If plasticity bricks are burned then it will gets
damaged. So before burning drying should be
done
 During drying bricks are arranged in manner of
circulation of air
 Drying period 3 – 10 days

53. Burning:
Burning is done in clamps or kilns.
Clamps are temporary structure used for small
scale manufacturing
Kilns are permanent structure used for large scale
manufacturing
clamps
Clamps are in trapezoidal shape.
Short end in excavation & wider end raised at an
angle of 15˚.
Brick wall with mud is constructed on short end
and fuel is filled on floor.(70-80cm)
4-5 courses of raw bricks is laid with air circulation
then fuel is filled and bricks are laid again
Total height is 3-4m.
Burning period 3-6months with cooling
production rate 30,000 to 3 lakh bricks

54. Clamp

55. Advantages of clamp burning:
✓ Cheap & economical.
✓ No skilled labour & supervision required.
Disadvantages.
✓ Slow process.
✓ Quality is not uniform.

56. Kilns
Types of kilns:
Intermittent kilns
Continuous kilns.

57. Intermittent kiln
 Its include different process of loading,
burning, cooling and unloading
 Circular or rectangular shape in plan
 Constructed above or below the ground
level
 Temporary roof is provided and it is
removed during burning
 Production rate = 20, 0000

58. Intermittent up-draught kiln

59. Intermittent down-draught kiln:

60. Continuous kiln
 Large quantity of bricks produced regularly
 It is circular in shape with center portion built with
refractory bricks for fuel
 Permanent roof is installed so bricks produced in rainy
season also
 The arrangements is divided into 12 chambers with
main doors
 Chamber 1 – loading
 Chamber 2-5 – drying
 Chamber 6-7 – burning
 Chamber 8-11 – cooling
 Chamber 12 – unloading
 Fuel saving
 Uniform quality bricks
 8-9 billion bricks per annum

61. Bull’s trench kiln

62. Hoffman’s kiln

63. Tunnel kiln

64. Classification of bricks
First class:
It is table moulded type.
It have good shape.
It have sharp, straight, square edges
Smooth surfaces it had
Used in permanent high class work
It implies all qualities of good brick
Second class:
It is ground moulded brick.
Surface of brick is not uniform and smooth
It is not used without plastering.

65. Third class:
Ground moulded and burned in clamp
Hardness is low.
Edges are not uniform.
Used in unimportant temporary structures and dry
places
Fourth class:
over burnt brick.
It have irregular shape and black in color.
It used as a coarse aggregate in concrete for floor,
foundation, road etc.,
Some times stronger than first class bricks

66. Properties of bricks:
❖ Should be compact, free from cracks and having
sharp edges and smooth surfaces
❖ Red in colour
❖ Water absorption should not exceed 20% by
weight.
❖ No impression should be left when scratched with
finger nail.
❖ Should give clear ringing sound when struck with
two bricks
❖ Size should be 200mm X 100mm X 100mm.
❖ Bricks should not break when dropped from 1m
height
❖ Broken brick should show homogeneous & free
from voids.
❖ Compressive strength should not be less than
3.5n/mm2

67. Classification of special bricks

68. Bull nose brick:
For rounding off sharp corners.

69. Squint brick:
 Acute and obtuse angle wall

70. Dog leg bricks:
This type of bricks used for construct the walls inclined.

71. Birds mouth bricks:
It is used to make the inclination in all layers of the
brick work.

72. Plinth bricks:
It is used in plinth level or in door and windows jambs.

73. Coping bricks:
It is used to make the parapet wall beautiful and to
make the parapet wall inclination at top.

74. cornice bricks:
It gives good appearance to the roof .
Sloping joint in roof and wall

75. Gutter bricks:
It is used for the drainage in the roof edges.

76. Tapering bricks:
It is used to provide arch at the top of door and
windows.

77. Circular bricks:
It is used to construct chimneys.

78. Perforated bricks:
It have perforation of 10mm-15mm.
This perforations used to reduce the self weight.

79. 13.Keyard bricks:
Top and sides of brick frogs are provided.
It gives good bonding strength.

80. 14.Hollow bricks:
Holes are provided.

81. Compression strength of
bricks
 Common – 5 n/mm2
 First class – 14 n/mm2
 Second class – 7 n/mm2
 Minimum – 3.5 n/mm2

82. Test on bricks
Water absorption test
 Take dry weight of brick (w1)
 Immersed in water for 24 hrs
 Then take wet of brick (w2)
 Water absorption = (w2 – w1) / w1 x 100
 Not exceed 20 % of weight

83. Crushing strength
 Find out by compression testing machine
 Compressive strength = load / area (n/mm2)
 Minimum – 3.5 n/mm2
 Maximum – 14 n/mm2

84. soundness
 When two bricks struck with each other it emits
metallic ringing sound

85. Hardness
 When brick is scratch with finger nail, no impression is
made on good brick

86. Efflorescence
 No deposit is present in good brick when immersed in
water for 24 hrs
 Then the brick is said to be free from salts
 <10% = harmless
 <50% = moderate
 >50% = harmful

87. Structure
 When brick is examined it is homogenous and
compact

88. Size and shape
Standard size – 190 x 90 x 90 mm
Take 20bricks of standard size.
❖ Stack it in length wise.(3680mm-3920mm)
❖ Stack it in width wise.(1740mm-1860mm)
❖ Stack it in height wise.(1740mm-1860mm)

89. BIS classification
 AA class - 14 n/mm2
 A class - 10.5 n/mm2
 B class - 7 n/mm2
 C class - 3.5 n/mm2