Physical properties of Building materials.


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  • Provides for “full” bearing
    Seals between masonry units
    Adheres / bonds masonry units
  • Portland Cement
    Hydrated Lime
    Admixtures (optional)
    Head & Bed Joints
    SLIDE 4280-3
  • Molding process
  • No “standard” size
    “Normal” coursing - 3 bricks = 8”
    Larger sizes
    Custom Shapes & Colors
  • Sawn
  • Split-open
  • Veneer-finishing or coating layer
  • extrusion
  • Physical properties of Building materials.

    1. 1. PHYSICAL PROPERTIES OF BUILDING MATERIALS Mohammad Naser Rozy 3rd year Department of Civil Engineering NIT Rourkela
    2. 2. CONCRETE Ingredient – cement, water, small stones Strength – cheap, fireproof & weatherproof, molds any shape, strong in compression Weaknesses – cracks with temperature changes, weak in tension Applications – early arch bridges & domes
    3. 3. REINFORCED CONCRETE Type – fine-grained concrete with high-strength steel Ingredient – steel bars hidden in concrete Strength – low-cost, fireproof & weatherproof, molds any shape, strong in compression & tension Weaknesses – can crack as it cools & hardens Applications – bridges, dams, domes, buildings
    4. 4. BRICK Type – ordinary brick Ingredient – burned clay Strength – cheap, strong in compression Weaknesses – heavy, weak in tension Applications – walls of early skyscrapers and tunnels, domes
    5. 5. CAST IRON Type – cast iron Ingredient – iron with lots of carbon Strength – molds to any shape, strong in compression Weaknesses – weaker than steel in tension, breaks without warning Applications – arch bridges, cannons, domes
    6. 6. STEEL Type – high-strength steel Ingredient – iron with a touch of carbon Strength – one of the strongest materials used in construction, strong in compression & tension Weaknesses – rusts, loses strength in extremely high temperature Applications – cables in suspension bridges, buildings
    7. 7. ALUMINUM Type – aluminum alloy Ingredients – aluminum w/ magnesium & copper Strength – lightweight, doesn’t rust, strong in compression & tension Weaknesses – expensive Applications – airplane wings, boats, skyscrapers “skin”
    8. 8. WOOD Strength – cheap, lightweight, moderately strong in compression & tension Weaknesses – rots, swells and burn easily Applications – bridges, houses, 2 or 3-story bldgs
    9. 9. PLASTIC Type – high-strength plastic fabric Ingredients – long chain of molecules Strength – flexible, lightweight, long lasting, strong in compression & tension Weaknesses – expensive Applications – tent structures,
    10. 10. Introduction to Concrete Prof. P. K. Bhuyan Department of Civil Engineering NIT Rourkela
    11. 11. Concrete As A Material • Concrete, literally, forms the basis of our modern life: – – – – Roadways/transportation systems Infrastructure (bridges, dams, buildings) Harbor protection (breakwalls) Water distribution (pipes & conduit)
    12. 12. Concrete has deep roots in history: Wall at Palestrina, Italy, 1st Century BC
    13. 13. Roman Aqueduct & Pantheon
    14. 14. Grand Coulee Dam
    15. 15. Concrete • The word “concrete” originates from the Latin verb “concretus”, which means to grow together.
    16. 16. Concrete • is a mixture of portland cement, water, aggregates, and in some cases, admixtures. • The cement and water form a paste that hardens and bonds the aggregates together. • Concrete is often looked upon as “man made rock”.
    17. 17. REASONS WHY CONCRETE IS THE MOST WIDELY USED MATERIAL: • Concrete is one of the cheapest and most readily available materials • Concrete can be formed into a variety of shapes and sizes • Concrete possesses excellent resistance to water
    18. 18. Advantage of Concrete • We have the ability to cast desired shapes – Arches, piers, columns, shells • Properties can be tailored according to need (strength, durability, etc.) • Ability to resist high temperatures – Will maintain structural integrity far longer than structural steel • Does not require protective coatings • Can be an architectural & structural member at the same time
    19. 19. Concrete Structural Frame City of Arts and Sciences, Valencia, Spain
    20. 20. Properties of Quality Concrete • Workability (ease of placement; resistance to segregation; homogenous mass) • Consistency (ability to flow) • Durability • Strength • Chloride Penetration Resistance • Abrasion Resistance
    21. 21. Workability • Workability is the property that determines the ease with which freshly mixed concrete can be placed and finished without segregation. • Workability is difficult to measure but redi-mix companies usually have experience in determining the proper mix. • Therefore, it is important to accurately describe what the concrete is to be used for, and how it will be placed.
    22. 22. Durability • If acceptable materials are used, the properties of concrete, such as durability, freeze/thaw resistance, wear resistance, and strength depend on the cement mixture. • A mixture with a sufficiently low ratio of water to cement plus entrained air, if specified, is the most desirable. These properties--and thus the desired concrete quality--can only be fully achieved through proper placement and finishing, followed by prompt and effective curing.
    23. 23. The Nature of Concrete • It is a composite material • Aggregates are 65% - 80% of the volume – Fine aggregate: sand – Coarse aggregate: stone • Cement: General term & applies to any binder – – – – • Water Portland cement fly ash ground slag silica fume
    24. 24. Concrete Microstructure
    25. 25. The Purpose Of The Aggregates • Large aggregates: – provide density (fill space: cheap filler) – provide strength (hard material) • Fine aggregates: – fill small voids between large aggregates (reduce volume changes) – Increases strength of the cement binder
    26. 26. The Cement Matrix • Cement: – produces a crystalline structure – binds aggregates together • Water Uses for cement: Mortar = cement + sand + water Plaster = cement + lime + sand + water Grout = cement + sand + considerable amount of water Paste = cement + water
    27. 27. Water • needed for two purposes: – chemical reaction with cement – workability • • • • only 1/3 of the water is needed for chemical reaction extra water remains in pores and holes results in porosity Good for preventing plastic shrinkage cracking and workability • Bad for permeability, strength, durability.
    28. 28. Portland Cement • Portland cement was named for the Isle of Portland, a peninsula in the English Channel where it was first produced in the 1800's. • Since that time, a number of developments and improvements have been made in the production process and cement properties.
    29. 29. What is Portland Cement? • Raw limestone, clay & gypsum minerals are ground into powder & heated in kiln (1600 ° C) • Minerals interact at that temperature to form calcium silicates (clinker) • Available in five types, each with varying performance characteristics and uses
    30. 30. Portland Cement Manufacturing Process
    31. 31. Clinker
    32. 32. Hydration • Portland cement becomes cementitious when mixed with water • This reaction is referred to as hydration. • During hydration, a crystalline structure grows to form bonds • Hydration begins as soon as water meets cement • Rate of hydration increases with increased cement fineness
    33. 33. In Fact……. • Concrete does not gain strength by “drying out” • Concrete must have continuous free access to water to achieve its ultimate strength!!
    34. 34. Admixtures:
    35. 35. Admixtures • Admixtures are ingredients other than portland cement, water, and aggregates. • Admixtures are added to the concrete mixture immediately before or during mixing.
    36. 36. Admixtures • chemical – – – – set retarders set accelerators water reducing air entraining • mineral – fly ash – silica fume – slags
    37. 37. Admixtures: • Coloring Agent – are pigments or dyes mixed into topping to render/alter color evenly to concrete surface • Surface Sealing Agents – liquid waxes sprayed over the surface that is easily removed after curing. Prevents evaporation of water into a new concrete allowing hydration and seal the pores of concrete surface after it has hardened • Dispersal Agents- prevents bleeding of concrete from concrete.
    38. 38. Admixtures: • Bonding Agent – either metallic aggregate or synthetic latex to improve the bond between old and new concrete. • Gas Forming Agent – develops the potential strength of a concrete • Non-Skid Surfaces - use abrasive material in topping to produced un-slippery surface for pavement construction • Hardener – chemical/fine metallic aggregate improve the density of concrete surface subject to impact and wear.
    39. 39. Admixtures: Retarding admixtures• delays or extend the setting time of concrete especially during hot weather condition (hydration accelerates curing) allowing more time to place, consolidate and finish the concrete.
    40. 40. Admixtures: Accelerating admixtures• Speeds up the setting of concrete to reduce the whole curing period or for early removal of forms. • such as calcium chloride, are used to increase the rate of hardening--usually during cold weather.
    41. 41. Admixtures: Water Reducers (Super-Plasticizers)• Water can be reduced • Increases viscosity • Results in higher strength and more durable concrete due to reduced water
    42. 42. Air Entrainment Admixtures• All concrete contains “entrapped” air • Large bubbles • Large voids are undesirable for durability & permeability • Entrained air • Bubbles are microscopic in size & distributed through out concrete • Increases durability by providing “escape route” for freezing water as it expands When Do We Use Air Entrained Concrete? Concrete to be placed in exterior locations requires air entraining (water/freeze/thaw)
    43. 43. Entrapped Air Voids
    44. 44. Entrained Air
    45. 45. Water – Cement Ratio • Water cement ratio controls the strength, durability and water tightness of hardened concrete. • Based on Abram’s Law (D.A. Abrams, 1919) “the compressive strength of concrete is inversely proportional to the ratio of water to cement” • Too much water will weaken concrete after curing. • Little water is dense but causes difficulty in placement and workability of concrete.
    46. 46. Water – Cement Ratio • The Average water-cement ratio is 30 liters per 50 kg. of cement bag. • Excessive water causes bleeding and laitance. Bleeding (emergence of excess mixing water on the surface of newly placed concrete caused by settlement of solids within the mass) Laitance (milky deposit containing cement and fine aggregate on the surface of new concrete combined with bleeding, overworking of mix or improper finishing).
    47. 47. Control of Concrete Mixes: • Concrete is normally specified according to the compressive strength it develops depending on the type of cement used. If ordinary Portland (7 - 28 days) or high early strength (3 – 7 days) after placement • Two methods of testing concrete’s compressive strength: 1. Slump test 2. Compressive Cylinder Test
    48. 48. Control of Concrete Mixes: 1. Slump test – to measure the consistency of freshly mixed concrete. Where a concrete is placed at a slump cone ( 300 mm high with a respective top diameter and bottom is 100 mm and 200 mm) and tamped in a prescribed manner then lifted to determine the decrease in height expressed by vertical settling in cm/mm.
    49. 49. Slump Test • Inverted cone • fill it up with three layers of equal volume • rod each layer 25 times • scrape off the surface 100 300 200
    50. 50. Slump Test slump cone rod concrete
    51. 51. Slump test Ruler Slump
    52. 52. Placing Conditions Blinding Concrete; Shallow Sections; Pavements using pavers Mass Concrete; Lightly reinforced sections in Slabs, Beams, Walls, Columns; Floors; Hand placed Pavements; Canal lining; Strip Footings Heavily reinforced sections in Slabs, Beams, Walls, Columns; Slip form work; Pumped Concrete. Trench fill; In-Situ Piling Degree of Workability Slump (mm) Very Low See 7.1.1 Low 25-75 Medium 50-100 High 100-150 52
    53. 53. Factors affecting slump • water cement ratio w/c = weight of water / weight of cement • constant cement content – increase water content • increase slump • NO GOOD
    54. 54. Factors affecting slump •Paste Content Low paste content Harsh mix High paste content Rich mix
    55. 55. ball bearing effect-start starting height
    56. 56. ball bearing effect-end slump
    57. 57. Factors affecting slump • Aggregates – Grading: larger the particle size, the higher the slump for a given paste content
    58. 58. effect of aggregate size 1” 1” 1” Consider a single aggregate the size of 1”x1”x1”
    59. 59. Compute the surface area as you break up the particles block surface area = 1*1*6= 6 block surface area = 0.5*0.5*6=1.5 volume = 1 cubic in surface area = 6 square inches volume = 1 cubic in surface area = 1.5*8= 12 square inches
    60. 60. Break it up further
    61. 61. Compute the surface area surface area = 0.25*0.25*6*8*8=24 0.5 in 0.25 in
    62. 62. Larger particles, less surface area, thicker coating, easy sliding of particles
    63. 63. Smaller particles, more surface area, thinner coating, interlocking of particles
    64. 64. Effect of aggregate size size # of particles volume surface area 1" 1 1 cubic inch 6 square inches .5" 8 1 cubic inch 12 square inches 0.25 64 1 cubic inch 24 square inches 0.125 512 1 cubic inch 48 square inches
    65. 65. Angularity and surface texture of aggregates angular and rough aggregate smooth aggregate river gravel
    66. 66. Bleeding
    67. 67. Water accumulation on surface Examine the concrete surface
    68. 68. Temperature fresh concrete aggregates paste
    69. 69. Interaction between bleeding and evaporation Evaporation surface water Bleed water Bleed water = evaporation
    70. 70. Bleeding and its control • Creates problems: – – – – poor pumpability delays in finishing high w/c at the top poor bond between two layers causes lack of fines too much water content Remedies more fines adjust grading entrained air reduce water content
    71. 71. Causes of Plastic Shrinkage Cracking • water evaporates faster than it can reach the top surface • drying while plastic • cracking
    72. 72. Too much evaporation leads to surface cracking Evaporation no surface water drying Bleed water < Evaporation
    73. 73. Plastic Shrinkage Cracking-Remedies • Control the wind velocity • reduce the concrete’s temperature – use ice as mixing water • increase the humidity at the surface – fogging – cover w/polyethylene – curing compound • Fiber reinforcement
    74. 74. Free Shrinkage, causes volume change, but no stresses before shrinkage After Shrinkage
    75. 75. Restrained Shrinkage- creates stresses, which may cause cracking
    76. 76. Restrained shrinkage cracking Parallel cracking perpendicular to the direction of shrinkage
    77. 77. Curing • The time needed for the chemical reaction of portland cement with water. • concrete after 14 days of curing has completed only 40% of its potential. • 70 % at 28 days.
    78. 78. Curing tips • • • • • • ample water do not let it dry dry concrete = dead concrete, all reactions stop can not revitalize concrete after it dries keep temperature at a moderate level concrete with flyash requires longer curing
    79. 79. Temperature effects on curing • The higher the temperature the faster the curing • best temperature is room temperature • strongest concrete is made at temperature around 5 C.(not practical) • If concrete freezes during the first 24 hrs., it may never be able to attain its original properties.
    80. 80. Temperature effects on curing • real high temperatures above 50 C can cause serious damage since cement may set too fast. • accelerated curing procedures produce strong concrete, but durability might suffer.
    81. 81. Two general methods of curing can be used: • Keep water on the concrete during the curing period. These include – – – – ponding or immersion, spraying or fogging, and saturated wet coverings. Such methods provide some cooling through evaporation, which is beneficial in hot weather.
    82. 82. • Prevent the loss of the mixing water from concrete by sealing the surface. Can be done by: – covering the concrete with impervious paper or plastic sheets, – applying membrane-forming curing compounds.
    83. 83. Testing of concrete • Concrete testing can broadly classified in to two major divisions. Green (Fresh) concrete Tests. • – Workability tests 1. 2. 3. 4. 5. 6. 7. 8. 9. Slump test Compacting factor test ASTM flow test Remoulding test Vebe Test Flow test Ball penetration test Nasser’s K-test Two point tests
    84. 84. Testing of concrete • Hardened concrete tests. – Strength in compression • Cube test (British Standard1881 : Part 111 :1983) • Cylinder test (BS 1881 : Part 110 :1983) (ASTM C 192-90a – Flexural strength test – Tensile test
    85. 85. Compression Tests Three types of compression test specimens are used: cubes, cylinders, and prisms. Cubes are used in Great Britain, Germany and many other countries in Europe. Cylinders are the standard specimens in the Unites States, France, Canada, Australia and Newzeland. In Scandinavia tests are made on both cubes and cylinders. The tendency nowadays, especially in research is to use cylinders in preference to cubes.
    86. 86. Strength Development and Strength Measurement • Aggregates “glued” together by cement paste to form concrete • Cement hydration is a chemical reaction which requires water • Strength gain reflects degree of hydration • Strength gain depends on – – – – Type of cement Temperature history – temperature and time Curing Admixtures
    87. 87. Factors Affecting Compressive Strength at 28 days • • • • • • Aggregate content Cement type and fineness Water/cement ratio Degree of compaction Extent of curing Temperature
    88. 88. Strength Measurement • 100mm or 150mm cubes at 7 and 28 days • 300mm x 150mm cylinders at 7 and 28 days (note ratio 2:1 and circular in plan) • Other tests – direct tension, bending and cores • Non-destructive testing
    89. 89. Cube Making: • Cube making: • Prime objectives – to achieve full compaction – avoid loss of moisture – keep at proper temperature when in curing tank • Use proper tools. • Advantage of cube shape is ease of making accurate sides.
    90. 90. Cube Making
    91. 91. Specifications • Cube Curing and Cube Testing • Cube Reports and Cube Failures
    92. 92. Cube Curing and Cube Testing • • • • Cube Curing: De-mould (take the mould out) when stability of cube allows. Prevent loss of moisture before placing in curing tank. Loss in strength due to initial drying out is unrecoverable. No provision for in-situ cubes. Give temperature matched curing.
    93. 93. Cube curing
    94. 94. Cube Testing • After curing process, cubes were tested by compressive strength machine as shown in the figure to measure the compressive load at which cubes will fail .
    96. 96. Compressive strength testing of Concrete cubes
    97. 97. Criteria for cube failures • A strength (the characteristic 28-day strength) is specified based on design – the concrete Grade • In compression test, two tested cubes at 28 days = one result – Provided difference between individual results is within 15% of average • Individual cube result: – every individual result must be greater than the characteristic -3MPa
    98. 98. Concrete Cube Test Result Variability • Variability – 28 day cube results have a mean strength and a standard deviation • For an expected 5% defective level, the target mean strength is the specified characteristic strength plus 1.64 times the standard deviation • Ensure actual mean is greater than target mean strength
    99. 99. Failure modes - Normal
    100. 100. Failure modes - Abnormal
    101. 101. Cylinder Test • A quality control test based on 7–28 days curing period to determine the compressive strength of a concrete specimen. •The standard cylinder is 150 mm diameter, 300 mm long and is cast in a mould generally made of steel or cast iron. The cylinder specimens are made are compacted either in three layers using a 16 mm diameter rod or in two layers by means of a vibrator. •Details of procedure are prescribed in ASTM Standard C192-76.
    102. 102. Cylinder Compressive Tests •After top surface of the cyliner has been finished by means of trowel, the cube is stored undistributed for 24 hours at a temperature of 18 to 22 º C and relative humidity of not less than 90 percent. At the end of this period the mould is stripped and the cylinder is further cured in a water at 19 to 21º C . •The test is generally performed at 28 days but it also perform additional test at 3 and 7 days. In compression test, the cylinder is placed with the faces in contact with the platens of the testing machine, i.e. the position of the cube when tested is at right angles to that as-cast. •The load on the cylinder should be applied at a constant rate of stress equal to 0.0250 KN/sq. meter/ sec
    103. 103. © Dr. Mohamed Abdallah El-Reedy
    104. 104. Consolidation of Concrete: • The process of eliminating voids other than entrained air within newly placed concrete and ensuring close contact of the concrete with form surfaces and embedded steel reinforcement. Through : vibration, spading and rodding Excessive vibration causes segregation (separation of coarse aggregate from mortar causing excessive horizontal movement making a free fall mix) Excessive vibration also causes stratification (separation combined with excessive wetting into horizontal layers where lighter material migrate towards the top)
    105. 105. Different Process of Mixing Concrete: • Manual – flat surface with shovels and buggy • Small Power – a manual mixing rotating drum • Bagger Mixer – equipped with diesel engine and pump operated mechanical mixing drum (1 or 2bags) or rotating mixing drum at the back of a truck.
    106. 106. Method of Transporting a Concrete: • Ready Mixed- concrete mixed at batch plant for delivery by an agitator to construction site.
    107. 107. Method of Transporting a Concrete: • Shrink Mixed – concrete partially mixed at the batch plant then mixed completely in a truck mixed en route to construction site. • Transit Mixed – concrete dry batch at a batch plant & mixed at the truck mixer en route to construction site.
    108. 108. Method of Transporting a Concrete: • Gunite – or “shotcrete” for lightweight construction, where concrete mix is pumped through a hose and sprayed at high velocity over reinforcement until desired thickness is reached.
    109. 109. Concrete-Applications • With proper materials and techniques, concrete can withstand many acids, milk, manure, fertilizers, water, fire, and abrasion. • Concrete can be finished to produce surfaces ranging from glass-smooth to coarsely textured, and it can be colored with pigments or painted.
    110. 110. • Concrete has substantial strength in compression, but is weak in tension. • Most structural uses, such as beams, slabs, and tanks, involve reinforced concrete, which depends on concrete's strength in compression and steel's strength in tension.
    111. 111. • When specifying and ordering concrete, the customer should be prepared to discuss such things as: – 1. Amount of concrete required, – 2. use of the concrete, – 3. type of cement,
    112. 112. – – – – – – – 4. minimum amount of cement per cubic meter 5. maximum water-cement ratio 6. any special admixtures, 7. amount of air entrainment, 8. desired compressive strength, 9. amount of slump, and 10. any special considerations or restrictions
    113. 113. CONSTRUCTION STONES Prof. P. K. Bhuyan Department of Civil Engineering NIT Rourkela
    114. 114. TOPICS  Stone Masonry – – – – – Stone as a Construction Material Classification of Stone Cutting and Dressing of Stones Construction of Stone Masonry Comparison between Brick and Stone masonry
    115. 115. Stone a natural, hard substance formed from minerals and earth material which are present in rocks. Rock the portion of the earth’s crust having no definite shape and structure
    116. 116. To qualify as a construction material, stone should have the following qualities:
    117. 117. Strength: Most types of stone have more than adequate compressive strength. The shear strength of stone, however, is usually about 1/10 of its compressive strength
    118. 118. Hardness: hardness is important when stone is used for flooring, paving, and stair treads.
    119. 119. Hardness: Talc, easily scratched with the thumb-nail: 1 Gypsum, scratched by the thumb-nail: 2 Calcite, not scratched by thumb-nail but easily cut by knife: 3 Fluorite, can be cut by knife with greater difficulty than calcite: 4 Apatite, can be cut only with difficulty by knife: 5 Orthoclase, can be cut w/ knife w/ great difficulty on thin edges: 6 Quartz, not scratched by steel, scratches glass: 7 Topaz: 8 Sapphire: 9 Diamond: 10
    120. 120. Durability: Resistance to the weathering effects of rain, wind, heat, and frost action is necessary for exterior stonework
    121. 121. Workability: A stone’s hardness and grain texture must allow it to be quarried, cut and shaped
    122. 122. Density: A stone’s porosity affects its ability to withstand frost action and staining
    123. 123. Density: Porosity of Stones 24-hours Water Absorption of Stones by Volume
    124. 124. Appearance: Appearance factors include color, grain, and texture
    125. 125. Quarrying and Producing Building Stones  Produced by blasting or cutting - Irregular-sized stone is produced by blasting the rock, the larger pieces are cut into smaller units for use as an exterior finish, rest is crushed and sorted into various sizes as aggregates - Most of the dimensional stones used in building construction are produced by cutting large blocks in the quarry - Cut with diamond belt saws; rubber air bags inflated in the saw cut to break it away and then the separated rock is lowered onto prepared stone chips cushion - Thereafter it is cut into smaller sizes and transported by front-end loaders to the mill for further processing
    126. 126. CLASSIFICATION OF STONES (according to geological origin):  Igneous rock  Sedimentary rock  Metamorphic rocks
    127. 127. Igneous rock is formed as a result of cooling of the molten rock to solid state - It is nonporous, hard, strong and durable Igneous rock also known as primary, un-stratified or eruptive rocks
    128. 128.  Granite : Consists mainly of quartz, feldspar, mica, and other colored minerals; colors include black, gray, red, pink, brown, buff, and green  Serpentine: Main ingredient is serpentine; color ranges from olive green to greenish black, is fine grained and dense  Basalt : Color ranges from gray to black; used mainly for paving stones and retaining walls
    129. 129. Granite  Non-porous, hard, strong, durable  Color Range  Surface Textures  Sources  Primary Uses 133
    130. 130. Polished Surface Rough Texture 134
    131. 131. Shape Flat to Round 135
    132. 132. TYPES OF BUILDING STONES Serpentine – igneous with mineral serpentine. Typically olive green to greenish black but impurities may color the rock. Used only for interiors due to weathering
    133. 133. Sedimentary rock is formed by the deposition of sediment by water, wind or glacier, results in sandstone, limestone and shale
    134. 134. Sedimentary rocks are also known as aqueous or stratified rocks Sandstone: Sedimentary rock composed of sand sized grains made of silica, iron oxide and clay - Colors include gray, brown, light brown, buff, russet, red, copper, and purple Limestone: Sedimentary rock composed of calcite and dolomite - Three types: oolitic, dolomitic and crystalline Has high compressive strength - Used for building stones and for paneling Shale: Derived from clays and silts; weak along planes and is in thin laminations - High in limestone and color varies from black to red, yellow, and blue
    135. 135. TYPES OF BUILDING STONES Sandstone – class of rock of cemented silica grains with texture ranging from very fine to very coarse. Colors vary from buff, red and light brown. Porous where as 30% of volume composed of pores
    136. 136. TYPES OF BUILDING STONES Limestone – sedimentary rock like dolomite, no cleavage lines, low in absorption, smooth, uniform in structure & composition. High compressive & tensile strength Used for: wall & floor surfaces
    137. 137. Limestone with Granite 141
    138. 138. TYPES OF BUILDING STONES Travertine – sedimentary rock, pleasing texture with small natural pockets on a cut surface. Used for: interior decorative stone
    139. 139. Metamorphic rocks has undergone a change in structure, texture, or composition due to the natural agencies, as heat and pressure, especially when the rock becomes harder and more crystalline, as marble and slate
    140. 140. Metamorphic rocks: Examples of Transformation of Rocks
    141. 141. Metamorphic Rock Marble Slate 145
    142. 142. TYPES OF BUILDING STONES Marble – metamorphic rock, a re crystallized limestone forming into carrara, parian, onyx and vermont. Used for: flooring wall & column facing
    143. 143. Marble - Exterior Application 147
    144. 144. TYPES OF BUILDING STONES Slate Rock – metamorphosis of clays and shale's deposited in layers. May be separated into thin, tough sheets called slates . Colors are black, green red, grey, or purple. Used for: flooring window sills stair treads & facing
    145. 145. Slate Flooring 149
    146. 146. Other Metamorphic Rocks Used In Stone Masonry  Quartzite: It is a variety of stone composed of mainly granular quartz cemented by silica, color varies from brown, buff, tan, ivory, red through gray  Schist: Made of silica with smaller amounts of iron oxide and magnesium oxide - Color varies from blue, green, brown, gold, white, gray, and red
    147. 147. STONE CONSTRUCTION Largely used as facing for building material with steel and concrete frames. 151
    148. 148. Application Categories : 1. 2. 3. 4. Paneling Ashlars Rubblework Trim
    149. 149. Paneling – thin slabs of stone cut to dimension and thickness to cover back up walls and provide finished exterior  Running Bond - a masonry bond formed when all units are laid in stretcher position, with a half-unit overlap
    150. 150. Paneling – thin slabs of stone cut to dimension and thickness to cover back up walls and provide finished exterior  Stack Bond - a masonry bond formed when there is no overlapping of all units and all horizontal & vertical joints are aligned
    151. 151. Ashlar Masonry  In this type properly dressed stones are used. 1. Ashlar fine or course ashlar masonry 2. Random coursed ashlar masonry 3. Rough tooled ashlar masonry 4. Rock or quarry faced ashlar masonry 5. Chamfered ashlar masonry 6. Block in course masonry 7. Ashlar facing
    152. 152. Ashlars – work requires the use of cut stone that includes broken ashlars, regularly / irregularly coursed.  Coursed Ashlar - Ashlar masonry laid out in courses of equal height; blocks of various sizes may be combined to make up the height of the course
    153. 153. Ashlars – work requires the use of cut stone that includes broken ashlars, regularly / irregularly coursed.  Random Ashlar - Ashlar masonry laid without regular courses but with an overall effect of horizontal orientation
    154. 154.  Rubble Masonry  In this type undressed or roughly dressed stones are used 1. Un-coarsed Rubble Masonry 2. Random Rubble Masonry 3. Coursed Rubble Masonry 4. Dry Rubble Masonry
    155. 155. Rubble - consists of rough fragments of broken stone that have at least one good face for exposure in a wall.
    156. 156. Rubblework – random & no attempt to produced an orderly course either horizontal or vertical.. Small spaces are filled with smaller stones.  Coursed Rubble - Fieldstone or roughly dressed stone, with or without mortar, assembled to give a effect of courses
    157. 157. Rubblework – random & no attempt to produced an orderly course either horizontal or vertical.. Small spaces are filled with smaller stones.  Fieldstone - Stone found on the ground (i.e., not quarried) that is a suitable size and shape for use as drywall or rubble masonry
    158. 158. Dimension stone - is quarried and squared stone 2’ or more in length and width and of specified thickness, used commonly for wall panels, cornices, copings, lintels and flooring.
    159. 159. Trim – stones cut for specific purposes like:  Corbel  Cornice  Drip Stone  Throating  Coping  Frieze  Spalls
    160. 160.  Corbel – It is a piece of stone projected outside of a wall to provide support to a structural member of the Roof or Floor. DIAGRAM  Cornice – It’s a large course of stone masonry provided at the ceiling level of roof, projected outside of wall.  Drip Stone – A projected stone with toothing at undersurface. It is provided to through the rain water off the wall.
    161. 161. Throating – The process of cutting groves in – Soffits of sills – Drip stones – Coping – String course etc. – Its purpose is to avoid the entry of rain water.  Coping – It is a special course provided at the top of a wall to avoid entry of rain water in wall.  Frieze – The stone course provided below the cornice is called frieze 
    162. 162. Stone Finish  Rusticated - A term describing stone masonry with a recessed cut margin, so a channel is formed when the blocks are aligned
    163. 163.  Sand Finish - A stone finish that is granular and moderately smooth, varying with the characteristics of the specific stone
    164. 164.  Sawn Face - A term describing stone exhibiting the marks left by the saw used to cut it
    165. 165.  Rock Face - A stone finish with emphasized face-plane shifts and rough corners, exaggerating the natural look of the stone
    166. 166.  Split Face - A stone finish exhibiting the natural quarry texture resulting from splitting the stone
    167. 167. Flagstone - refers to flat stone slabs used for flooring and horizontal surfacing.
    168. 168. Stone Pavers  Cobble stone - A stone used in paving. It may be rectangular, or naturally rounded
    169. 169.  Durex Blocks - Roughly cubed, usually granite blocks used for paving
    170. 170. Lifting Appliances for Stone Masonry Pin Lewis Chain Lewis Lewis Chain Dogs Three Legged
    171. 171. Stone vs Brick  Similarities: – Both stacked – Mortar Joints  Differences: – Shape: » Brick molded - Stone Cut and Carved – Physical Properties: » Brick made/controlled – Stone provided by nature 176
    172. 172. Brick & Brick Masonry Dr. P. K. Bhuyan NIT Rourkela
    173. 173. Definitions Masonry  It is used for the work of a mason.  Mason is a person who built structures with construction materials. Masonry Units  It is an artificially prepared regular shape block used in the masonry works. Like ….  Brick in brick masonry  Stone block in stone masonry  Concrete block in Block masonry
    174. 174. History of Bricks: Bricks are one of the oldest types of building blocks. They are an ideal building material because they are relatively cheap to make, very durable, and require little maintenance. A brick is a block of ceramic material used in masonry construction, usually laid using various kinds of mortar. Bricks dated 10,000 years old were found in the Middle East. Examples of the civilizations who used mud brick are the ancient Egyptians and the Indus Valley Civilization, where it was used exclusively. In particular, it is evident from the ruins of Buhen, Mohenjo-Daro and Harappa. The first sun-dried bricks were made in Mesopotamia (what is now Iraq), in the ancient city of Ur in about 4000 BC
    175. 175. Advantages of bricks : * Brick will not burn, buckle or melt * Brick will not rot * Brick will not rust and corrode * Brick will not dent (depress). * Brick will not fade from the Sun's UV Rays. * Brick will not be damaged by high winds, rain or hail. •Brick will not require constant maintenance. •* Brick will not limit your personal expression. * Brick will not limit your design options.
    176. 176. General Characteristics of Bricks Brick is made of clay or shale formed, dried and fired into a durable ceramic product. There are three ways to form the shape and size of a brick: extruded (stiff mud), molded (soft mud) and drypressed.  The majority of brick are made by the extrusion method. Brick achieves its color through the minerals in the fired clay or through coatings that are applied before or after the firing process. This provides a durable color that never fades or diminishes. Brick shrink during the manufacturing process as vitrification occurs. Brick will vary in size due to the manufacturing process.
    177. 177. The method used to form a brick has a major impact on its texture. Sand-finished surfaces are typical with molded brick. A variety of textures can be achieved with extruded brick. manufacturing facilities near clay sources to reduce transportation, by recycling of process waste, by reclaiming land where mining has occurred, and by taking measures to reduce plant emissions. Most brick are used within 500 km of a brick manufacturing facility.
    178. 178. Raw material for clay: Clay is one of the most abundant natural mineral materials on earth. For brick manufacturing, clay must possess some specific properties and characteristics. Such clays must have plasticity, which permits them to be shaped or molded when mixed with water; they must have sufficient wet and air-dried strength to maintain their shape after forming. Also, when subjected to appropriate temperatures, the clay particles must fuse together.
    179. 179. Types of Clay : Clays occur in three principal forms, all of which have similar chemical compositions but different physical characteristics. Surface Clays. Surface clays may be the upthrusts of older deposits or of more recent sedimentary formations. As the name implies, they are found near the surface of the earth. Shales. Shales are clays that have been subjected to high pressures until they have nearly hardened into slate. Fire Clays. Fire clays are usually mined at deeper levels than other clays and have refractory qualities. Surface and fire clays have a different physical structure from shales but are similar in chemical composition.
    180. 180. All three types of clay are composed of silica and alumina with varying amounts of metallic oxides. Metallic oxides act as fluxes promoting fusion of the particles at lower temperatures. Metallic oxides (particularly those of iron, magnesium and calcium) influence the color of the fired brick. The manufacturer minimizes variations in chemical composition and physical properties by mixing clays from different sources and different locations in the pit. Chemical composition varies within the pit, and the differences are compensated for by varying manufacturing processes. As a result, brick from the same manufacturer will have slightly different properties in subsequent production runs. Further, brick from different manufacturers that have the same appearance may differ in other properties.
    181. 181. Raw Material
    182. 182. Bricks Manufacture - 4 stages Material preparation Manufacturing drying Firing Preparation: material (clay) washed and grinding (fineness) Sample of grinding machine for clay Sample of crushing machine 191
    183. 183. Brick Manufacturing : Clay is grinded with 15% of water. The clay is then pushed through the mould base to take the shape. After that, Clay is cut to get a standard size and shape of brick using wire. Sometimes, bricks are produced using big mould in which clay will be pressed using hydraulic machine or without hydraulic press. 192
    184. 184. “Molded” or Handmade”  solid units  pressed into fiberglass, wood or steel molds  used to be by hand, now machines  sand or water coated molds to release bricks  usually rougher surface and edges
    185. 185. After bricks in form, identification or perforation to the bricks. Drying : Wet unit bricks are then dried by keeping them in space or in a room with controlled temperature to make sure that bricks will be complete dry. Brick was compile before bring to the kiln 194
    186. 186. Firing : Dry bricks, are then compiled in kiln for firing process with 600oC as initial temperature. This is to burn the carbon and sulfur that have remained. After that, temperature is increased to 900oC to start the vetrification process. Normally, vitrification process occurrs at around 800oC. Bricks become hard/strong after vitrification process. 195
    187. 187. Bricks Bricks manufacturing process flow
    189. 189. Manufacturing
    190. 190. Manufacturing
    191. 191. Setting
    192. 192. Firing Process
    193. 193. Packaging
    194. 194. Important Components Of Brick Making
    195. 195. Important Components Of Brick Making 2. The Raw Materials
    196. 196. This wood sheet is used as the stand for bricks, because when the bricks are ready - they are wet, so we cant touch them and that’s why we are using this wood stand.
    197. 197. MIX THE MATERIALS They are mixing the materials: chopped stone, cement,white sand and water.
    198. 198. START THE WORK First, arrange the wood sheet in the machine, below the two holes. Secondly, pull the wood handle and move it round so you can see the two holes
    199. 199. Then fill the material on the two holes, and manage it equally.
    200. 200. Then pull up the handle and move it around like this. Afterwards, get back to the old position and push the handle harder in down way.
    201. 201. Then pull it up... get the shape!
    202. 202. Take the bricks out of the machine.
    203. 203. Arrange the bricks in a line.
    204. 204. Style of the bricks arrangement when they are wet.
    205. 205. Remove the wood stand and arrange it in different styles..
    206. 206. Next morning, the water should be applied to the brick and they become more harder. Transport facilities of the material..
    207. 207. Different kinds of bricks.
    208. 208. PROPERTIES OF BRICKS The most important properties of brick are 1) durability, 2) color, 3) texture, 4) size variation, 5) compressive strength and 6) absorption. Durability: The durability of brick depends upon achieving incipient fusion and partial vitrification during firing. Because compressive strength and absorption values are also related to the firing temperatures, these properties, together with saturation coefficient, are currently taken as predictors of durability in brick specifications. However, because of differences in raw materials and manufacturing methods, a single set of values of compressive strength and absorption will not reliably indicate the degree of firing.
    209. 209. Texture: Coatings and Glazes : Many brick have smooth or sand- finished textures produced by the dies or molds used in forming.  A smooth texture, results from pressure exerted by the steel die as the clay passes through it in the extrusion process. Most extruded brick have the die skin removed and the surface further treated to produce other textures using devices that cut, scratch, roll, brush. Brick may be tumbled before or after firing to achieve an antique appearance.
    210. 210. Color: The color of fired clay depends upon its chemical composition, the firing temperatures and the method of firing control. Of all the oxides commonly found in clays, iron probably has the greatest effect on color. Regardless of its natural color, clay containing iron in practically any form will exhibit a shade of red when exposed to an oxidizing fire because of the formation of ferrous oxide. When fired in a reducing atmosphere, the same clay will assume a dark (or black) hue. Creating a reducing atmosphere in the kiln is known as flashing or reduction firing. Given the same raw material and manufacturing method, darker colors are associated with higher firing temperatures, lower absorption values and higher compressive strength values. However, for products made from different raw materials, there is no direct relationship between strength and color or absorption and color.
    211. 211. Size Variation Because clays shrink during both drying and firing, allowances are made in the forming process to achieve the desired size of the finished brick. Both drying shrinkage and firing shrinkage vary for different clays, usually falling within the following ranges: Drying shrinkage: 2 to 4 percent  Firing shrinkage: 2.5 to 4 percent  Firing shrinkage increases with higher temperatures, which produce darker shades. When a wide range of colors is desired, some variation between the sizes of the dark and light units is inevitable. To obtain products of uniform size, manufacturers control factors contributing to shrinkage. Because of normal variations in raw materials and temperature variations within kilns, absolute uniformity is impossible. Consequently, specifications for brick allow size variations.
    212. 212. Compressive Strength and Absorption Both compressive strength and absorption are affected by properties of the clay, method of manufacture and degree of firing. For a given clay and method of manufacture, higher compressive strength values and lower absorption values are associated with higher firing temperatures. Although absorption and compressive strength can be controlled by manufacturing and firing methods, these properties depend largely upon the properties of the raw materials.
    213. 213. Tests on bricks: Clay Masonry Units -ASTM C 67, Standard Test Methods for Sampling and Testing Brick and Structural Clay Tile Procedures for the sampling and testing of brick and structural clay tile. Tests include modulus of rupture, compressive strength, absorption, saturation coefficient, effect of freezing and thawing, efflorescence, initial rate of absorption and determination of weight, size, length change, and void area.
    214. 214. Brick British Specification Recommends LENGTH (L) Minimum Length = 8-5/8” Maximum Length = 8-7/8 ” WIDTH (W) Minimum Width = 4-1/8 ” Maximum Width = 4-1/4 ” DEPTH (D) Minimum Depth = 1-15/16 ” Maximum Depth = 2-15/16 ” L D W
    215. 215. Brick Positions: Stretcher Header Soldier Shiner Rowlock Sailor
    216. 216. Definitions Frog  Arrises  The edges formed by the intersection of plane surfaces of a brick are called arrises.  Frog  The depression provided in the face of a brick during its manufacturing is called the frog.  Course each horizontal layer of bricks laid in mortar is called course. Courses Arises
    217. 217. Definitions Quoins Perpends  The external corners of a wall are called Quoins. And the bricks forming quoins are called quoin bricks. E.g quoin header or quoin stretcher. Perpends The imaginary vertical lines which includes vertical joints are called Perpends. Quoin Header Quoin Stretcher
    218. 218. Definitions Header Brick laid with its width in elevation is called header. In a course in which all bricks are header is called heading or header course. Stretcher Brick laid with its length in elevation is called stretcher. In a course in which all bricks are stretcher is called stretcher or stretching course.
    219. 219. Definitions  Closure  Closure bricks are prepared by cutting standard brick across length or in different ways to fulfill the requirements of bond in straight walls, corners, junctions or crosses is called closures. They are of four types  Queen closure  King closure  Bevelled closure  Mitered closure  Brick bats  Brick bats are prepared by cutting standard brick across width. They are of four types  Three quarter bat  Half or square bat  Quarter bat  Bevelled bat
    220. 220. Definitions Facing The external face of wall is called facing. Backing The unexposed or internal face of wall is called backing. Hearting The interior portion between facing and backing is called hearting.
    221. 221. Definitions Reveals It is the verticle sides of door or window opening from outside is called reveals. Jambs It is the verticle sides of door or window opening from inside is called jambs. Soffit The under surface of a lintel is called Soffit. It’s the horizontal surface. Sill The horizontal surface at the bottom side of a door or window opening is called sill.
    222. 222. Definitions Column  The isolated vertical load bearing member whose cross sectional dimensions are much lesser then its length is called column. Pillar  The isolated vertical non load bearing member used for ornamental purpose or as memorial is called pillar. Pier  The isolated vertical load bearing members used as an intermediate support of a series of arches is called pier. Pilaster  The thickened vertical load bearing member strengthening a wall is called pilaster. Stanchion  The vertical load bearing member constructed of rolled steel section is called stanchion.
    223. 223. Definitions Mortar The mixture of binding material and fine aggregate forming a workable paste is called mortar. Grout or slurry The thin paste of cement is called grout or slurry. It is used to fill the joints. Lintel A small horizontal member to span up small opening is called lintel. Copping It is provided at the top of a wall to avoid dampness.
    224. 224. Classification of Brick Masonry According to type of Mortar Pucca Masonry Pucca & Kutcha Masonry According to types of bricks First class brick Masonry Second class brick Masonry Third class brick Masonry Kutcha Masonry
    225. 225. Mortar Functions  Provides for full bearing  Seals between masonry units  Adheres / bonds masonry units  Aesthetics •20%± of wall area •Affects the color and texture of masonry wall •Mortar specified in testing standard ASTM C-270
    226. 226. Mortar Ingredients Portland Cement Hydrated Lime Sand Water Admixtures (optional)
    227. 227. Bond in brick masonry  It is the arrangement of bricks in each layer to avoid the continuity of vertical joints in any two adjacent courses.  NECESSITY OF BOND  Bond in brickwork is provided for the following reasons  To break the continuity of vertical joints in consecutive courses.  To ensure longitudinal and lateral strength of the masonry work.  To distribute the load uniformly over the structural mass.  To ensure the quality of work.  To ensure systematic work  To provide good esthetics  To economize the work.  REQUIREMENTS OF a GOOD BOND IN BRICK WORK  Bricks should be uniform in size.  Mortar thickness should be less than 10mm  Vertical joints in alternate courses should be in a single plumb line.  Header should be exactly in the middle of stretcher in two consecutive courses.  Brick bats should be avoided.
    228. 228. Types of bonds Following are the different types of bonds used in brick masonry work. BONDS IN MASONRY WALLS Header bond Stretcher bond English bond Flemish bond Facing bond Dutch bond BONDS IN MASONRY COLUMNS English bond Flemish bond
    229. 229. Wall Junctions  The places where the walls of same or different widths meets or crosses each other are called wall junctions. TYPES OF WALL JUNCTIONS  Two types  Straight junctions  Squint junctions  Straight junctions  The junctions formed when two walls crossing each other at right angle.  Corner junctions  Tee junctions  Cross junctions  Squint quoins  The corner formed when two walls are meeting at some angle.  Obtuse quoins  Acute quoins
    230. 230. Masons tools in Bick masonry Trowel Brick hammer Lines and pins Spirit level and water level Straight edge Plumb bob Mason;s square or guniya Tape (steel)
    231. 231. General Principles and precautions in Brick Masonry English bond should be used if not specified. Bricks used should be well burnt and should be uniform in size, shape and colour. For facing work selected bricks should be used. Curing of bricks should be done for at least 2 hours. Bricks should be laid with frogs pointing upward or as specified by the Engineer In charge. Mortar used in brick masonry should be of good quality. In walls greater than 9” or 0.225 m width hearting joints should be filled properly. Brick bats are avoided.
    232. 232. Reinforced brick Masonry The brick masonry done by embedding reinforcement in rich cement mortar is called Reinforced brick masonry. Reinforcement used may be in the form of Steel bars Hoop iron Wire mesh or XPM (expanded metal with specified LWM and SWM)
    233. 233. Constructions of Brick Masonry It is the art of laying bricks in a proper bond with specified mortar to form a structure. It involves the following activities… Selection of bricks Stacking of bricks Soaking of bricks Preparation of mortar (ASTM Specifications C 270, "Mortar for Unit Masonry“) Laying of bricks
    234. 234. Defects and Maintenance of Brick Masonry DEFECTS Due to Substandard materials Due to corrosion of metals Due to effect of sulphates Due to frost action Due to efflorescence MAINTENANCE Cleaning brick masonry Removing efflorescence Re-conditioning the brick masonry Repainting the brick masonry
    235. 235. More Bonds 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. Header bond Stretcher bond English bond Flemish bond Raking bond English Cross bond Hoop Iron Bond Facing bond Dutch bond Monk bond Brick on edge bond Silverlock’s bond
    236. 236. Header Bond 3/4 3/4 First course or Odd courses Second course or Even courses
    237. 237. Course: Continuous layer Wythe: Continuous vertical section
    238. 238. Basic Brickwork Terminology Head Joint Bed Joint Course - horizontal layer of brick
    239. 239. Basic Brickwork Terminology Header - Bonds two wythes together Wythe: vertical layer 1 unit thick Rowlock laid on face, end visible Stretcher - long dimension horizontal & face parallel to the wall Soldier - Laid on its end, face parallel
    240. 240. Corbel Shelf or ledge formed by projecting successive courses of masonry out from the face of a wall
    241. 241. Quions Stone blocks used to form strong corners.
    242. 242. English Bond
    243. 243. 2 courses of English bond
    244. 244. Flemish Bond
    245. 245. Flemish Bond
    246. 246. Lintel and load distribution
    247. 247. Brick Pilaster
    248. 248. Corner Junctions (English Bond & Flemish Bond)
    249. 249. Tee Junctions (English Bond & Flemish Bond)
    250. 250. Cross Junction & Squint Junctions
    251. 251. Squint Quoins (English Bond)*
    252. 252. Brick Work Brick arrangement in brick work 266
    253. 253. Brick work Brick arrangement in brick work 267
    254. 254. Brick Work Brick arrangement in brick work 268
    255. 255. Brick Work Brick arrangement in brick work 269
    256. 256. Brick Work Brick laying Material that was used in mortar (mix of cement or lime with sand or both Ratio; binder : sand = 1:3 Thickness or mortar normally in range 6.5mm 9mm 270
    257. 257. Brick Work Plastering These have been done after brick lying finishing. The purpose is to get a smooth surface and uniformity in color. The wall should scratch to get a rough surface that will easy when plastering work Materials that was used : lime, cement Portland, gypsum Plastering work should be in two layers, which one base layer and finishing layer. Base layer ; cement :Lime : sand = 1:2:8-9 @ 1:1: 5-6 @ cement : sand = 1:3 @ gysum : sand = 1:1-3 @ gypsum : lime : sand = 1:3:7-9 Finishing layer; lime : gypsum = 1: 0.25 - 0.5 271
    258. 258. Walk way Decorative of brick work 272
    259. 259. Advantages of brick 273
    260. 260. The End 278
    261. 261. Considerations in Choosing Brick process Molding Color Size Grade Type
    262. 262. However, most brick is………. EXTRUDED pushed through a dye & then cut by wire • • • hollow core formed into a column and cut to size with wires usually smoother surface and finer edges “kinda’ like square toothpaste”
    263. 263. Brick Masonry - Sizes and Shapes  No standard size  Normal coursing - 3 bricks h 8” (including mortar joints so it aligns with 8” block (CMU)  Larger sizes mostly for economy  Custom Shapes & Colors ($$$$$) =
    265. 265. Bitumen & Desirable Properties By Dr. P. K. Bhuyan NIT Rourkela
    266. 266. Overview  Pavement materials Soil (sub-grade, embankment) Aggregates (coarse, fine) Binders (Bitumen, cement) 284
    267. 267. Bitumen  Bitumen is a petroleum product obtained by the distillation of petroleum crude  Bitumen is a hydrocarbon material of either natural or hydrogenous origin, found in gaseous, liquid, semisolid or solid form  Highway construction: hydrocarbon material which are cementious in character 285
    268. 268. Bitumen 1. Natural product (lake asphalt, rock asphalt) 2. Fractional distillation of petroleum a. Asphalt cement (Penetration grade) b. Oxidised asphalt (softening point grade) c. Liquid asphalt 3. Tar: destructive distillation of coal 286
    269. 269. Liquid Bitumen  Cutback: the viscosity of bitumen reduced by volatile diluents (kerosene, diesel): slow, medium, rapid curing  Emulsion: bitumen is suspended in finely divided condition in an aqueous medium (water) and stabilized with an emulsifier: slow, medium, rapid setting 287
    270. 270. 1. Normal Bitumen Production  The portion of bituminous material present in petroleum may widely differ depending on the source  Almost all the crude petroleum's contain considerable amounts of water along with crude oil  Hence the petroleum should be dehydrated before the distillation 288
    271. 271. Petroleum distillation Flow Chart 289
    272. 272. Petroleum distillation 290
    273. 273. Types of Distillation Processes Fractional distillation In the fractional distillation the various volatile constituents are separated at successively higher temperatures without substantial chemical change The fractions obtained yield gasoline, naphtha, kerosene and lubricating oil and the residue would be petroleum bitumen Destructive distillation The material undergoes chemical changes under the application of extreme heat and pressure 291
    274. 274. Types of Distillation Processes Steam distillation 1. Steam distillation is employed to produce steam refined petroleum bitumen without causing chemical change 2. When the residue is distilled to a definite consistency without further treatment it is called as Straight-run Bitumen 292
    275. 275. Desirable Properties of Bitumen  It should be fluid enough at the time of mixing to coat the aggregate evenly by a thin film  It should have low temperature susceptibility  It should show uniform viscosity characteristics  Bitumen should have good amount of volatiles in it, and it should not lose them excessively when subjected to higher temperature 293
    276. 276. Desirable Properties of Bitumen  The bitumen should be ductile and not brittle  The bitumen should be capable of being heated to the temperature at which it can be easily mixed without any fire hazards  The bitumen should have good affinity to the aggregate and should not be stripped off in the continued presence off water 294
    277. 277. 2. Cutback Bitumen  Bitumen, the viscosity of which has been reduced by a volatile dilutent  Thus to increase fluidity at lower temperatures bitumen is blended with a volatile solvent  After the use of cutback, the volatiles get evaporated and binding property gets developed  For use in some constructions like, surface dressings, some type of bitumen macadam and soil-bitumen stabilization, it can be mixed at low temperatures 295
    278. 278. Continue….  The viscosity of cutback and the rate at which it hardens on the road depend on the characteristics and quantity of both bitumen and volatile oil used as the dilutent Types: classification based on rate of curing or hardening after application 1. Rapid Curing (RC) 2. Medium Curing (MC) 3. Slow Curing (SC) 296
    279. 279. Viscosity of Cutbacks Viscosity in seconds in tar viscometer Type and grade of Cutback 4mm orifice 25oC RC-0, MC-0 & SC-0 10mm orifice 40oC 25 to 75 RC-1, MC-1 & SC-1 10mm orifice 25oC 50 to 100 RC-2, MC-2 & SC-2 10 to 20 RC-3, MC-3 & SC-3 25 to 75 RC-4, MC-4 & SC-4 14 to 45 RC-5, MC-5 & SC-5 60 to 100 297
    280. 280. Continue….  Lower grade cutbacks like RC-0, RC-1 etc. would contain higher proportion of solvent  RC-0 & MC-0: 45% solvent, 55% bitumen  RC-5 & MC-5: 15% solvent, 85% bitumen 298
    281. 281. Continue….  Rapid Curing Cutbacks are bitumen's, fluxed or cutback with a petroleum distillate such as naphtha or gasoline which will rapidly evaporate after use  Medium Curing Cutbacks are bitumen fluxed to greater fluidity by blending with an intermediate-boiling-point solvent like kerosene or light diesel oil  Slow Curing Cutbacks are obtained either by blending bitumen with high-boiling-point gas oil, or by controlling the rate of flow and temperature of the crude during the refining 299
    282. 282. 3. Bituminous Emulsion  A liquid product in which substantial amount of bitumen is suspended in a finely divided condition in an aqueous medium and stabilized by means of one or more suitable materials.  Two phase system, one liquid being dispersed as fine globules in the other  Bitumen is broken up into fine globules and kept suspended in water  Small proportion of an emulsifier is used to facilitate the formation of dispersion and to keep the globules of dispersed binder in suspension 300
    283. 283. Continue….  Bitumen content of emulsion ranges from 40 to 60% and the remaining portion is water  Emulsifiers usually adopted are soaps, surface active agents and colloidal powders (1.5 to 1%)  Penetration values of bitumen grades that are emulsified for road construction are generally between 190-320  Manufactured emulsions stored in air tight drums  Used mainly in maintenance and patch works and also in wet weather conditions 301
    284. 284. Continue….  Bituminous Emulsion 1. Residue on sieving: not more than 0.25% by wt. of emulsion consists of particles greater than 0.15mm diameter 2. Stability of mixing: To test if emulsion breaks down and coats the coarse aggregates with bitumen too early before mixing is complete 3. Stability of mixing: To assess the stability of emulsions when the aggregate contains large proportions of fines with cement 302
    285. 285. Continue…. 4. Water Cement: To know the percentage of water in the emulsion which depends on the type of the emulsion 5. Sedimentation: Some sedimentation may occur when a drum of emulsion is left standing before use 6. Viscosity: Should be Low enough to be sprayed through jets or to coat aggregates in simple mixing 303
    286. 286. Continue…. Breaking of Emulsion  When applied on road, breaks down and the binder starts binding the aggregates, though the full binding power develops slowly as and when the water evaporates.  First sign of breakdown is change in color of film from chocolate brown to black  Rapid-set grades: Emulsion which break rapidly on coming in contact with aggregates  Medium-set grades: Which do not break spontaneously on coming in contact with aggregates but break during mixing or by fine mineral dust  Slow-set grades: When special emulsifying agents are used to make emulsion relatively stable 304
    287. 287. Quality Control Tests  Bitumen (Normal) 1. Penetration 2. Ductility 3. Softening point 4. Specific gravity 5. Loss on heating 6. Flash & Fire point 7. Viscosity 8. Solubility  Modified Bitumen (PMB, CRMB etc) 1. Elastic Recovery 2. Separation Difference 3. Tests on TFOT residue 305
    288. 288. Continue….  Cutback Bitumen 1. Viscosity test using specified orifice 2. 3. 4. 5. Penetration test Ductility test Solubility test Flash point test 306
    289. 289. Flexible Pavements 307
    290. 290. BITUMINOUS PAVEMENT CONSTRUCTION Bituminous construction are classified into four categories     Interface Treatments Thin Bituminous Surfacing Bituminous Surface Courses Bituminous Binder Courses 308
    291. 291. INTERFACE TREATMENTS  Prime Coat  Tack Coat  Crack Prevention Courses 309
    292. 292. PURPOSE OF PRIMING  To plug the capillary voids  To coat and bond loose materials on the surface  To harden or toughen the surface  To promote adhesion between granular and the bituminous layer 310
    293. 293. TACK COAT Purpose of Tack Coat:  To ensure a bond between the new construction and the old surface Use of Cutback:  It should be restricted for sites at subzero temperatures or for emergency applications 311
    296. 296. INSUFFICIENT TACK COAT 314
    297. 297. CRACKED SURFACE Map/Alligator Cracking Transverse Cracking 315
    298. 298. BITUMINOUS SURFACE DRESSING (BSD) BSD is provided over an existing bituminous or granular surface to serve as thin wearing coat. This may be one coat or two coats. The main functions of BSD are:  To serve as a thin wearing course of pavement  To prevent infiltration of surface water  To provide dust free pavement surface 316
    301. 301. SEAL COAT A. Liquid Seal Coat: comprising of a layer of binder followed by a cover of stone chipping B.Premixed Seal Coat: a thin application of fine aggregates premixed with bituminous binder 319
    303. 303. BITUMINOUS CONCRETE (BC) BC is a Dense Graded Bituminous Mix used as Wearing Course for Heavily Trafficked Roads  321
    304. 304. BITUMINOUS CONCRETE (BC) BC Mix consists of Coarse Aggregates, Fine Aggregates, Filler and Binder blended as per Marshall Mix Design  322
    305. 305. BITUMINOUS CONCRETE (BC) Quality control operations involved are:  Design of mix in laboratory, and control of mixing, laying and rolling temperatures Density, Marshall Stability, Flow, Air Voids, Bitumen Content, radiation of aggregates are controlled   Riding quality is a control 323
    306. 306. Freshly Laid BC layer BC Layer after Traffic 324 Movement
    307. 307. SEMI DENSE BITUMINOUS CONCRETE (SDBC) Wearing course on roads carrying moderate traffic, generally less than 10 msa  Lesser binder content when compared to BC  325
    308. 308. SDBC LAYER 326
    309. 309. COMPACTION OF BITUMINOUS MIXES  Lack of adequate compaction in field leads to reduce pavement life  Inadequate compaction of hot mix leads to early oxidation, ravelling, cracking and disintegration before its life expectancy is achieved 327
    310. 310. COMPACTION OF MIXES contd… • Lack of attention to the air voids requirement of compacted dense graded bituminous mixes is the most common cause of poor pavement performance • Laboratory compaction produces more density, hence 95-98% of laboratory density or 92% of theoretical density is preferred in the field 328
    311. 311. MASTIC ASPHALT  Mastic Asphalt is a mixture of Bitumen, Filler and Fine Aggregates in suitable proportions designed to yield a void less compact mass  It is heated to 200ºC  It solidifies into a dense mass on cooling to normal temperature  No compacting effort required 329
    312. 312. SEGREGATION IN MIX Segregation due to Single Drop 330
    313. 313. SEGREGATION IN BM MIX 331
    314. 314. PROPER LOADING 332
    315. 315. GOOD PAVEMENT SURFACE 333
    316. 316. DENSE BITUMINOUS MACADAM (DBM)  DBM is Closely Graded DBM is used as a Binder Course for pavements subjected to heavy traffic  Hydrated Lime or Cement shall be used as filler, if the mix fails to meet the water sensitivity  requirement 334
    317. 317. Wet Mix Macadam  Laying and compacting clean, crushed, graded aggregate and granular material, premixed with water, to a dense mass on prepared sub-grade or existing pavement  Thickness of single compacted Wet Mix Macadam layer shall not be less than 75 mm  Coarse aggregate shall be crushed stone  If crushed gravel is used, not less than 90% by Wt of gravel pieces retained on 4.75 mm sieve shall have at least two fractured faces  If water absorption value of coarse aggregate is greater than 2%, the soundness test shall be carried out as per IS:2386(Part-5) 335
    318. 318. TIMBER AS A BUILDING MATERIAL Dr. P. K. Bhuyan NIT Rourkela
    321. 321. Defects in Timber ‘Defect’, in this case, means anything that effects the structural integrity or appearance of timber.
    322. 322. Things that attack timber
    325. 325. Defects in timber Timber is a natural material that is prone to defects. One of these is the tendency to split if it is put under stress from rapid drying or de-lamination of the growth rings. These defects are all known as ‘Shakes’ Click your mouse once to continue
    326. 326. Shakes Click your mouse once to continue
    327. 327. HEART SHAKES
    328. 328. What other defects occur in timber? Blue stain sap heart pith juvenile Click your mouse once to continue
    329. 329. BOW
    330. 330. TWISTED GRAIN
    331. 331. KNOTS
    332. 332. WANE
    333. 333. SLOPE OF GRAIN
    334. 334. CUPPING DEFECTS
    335. 335. What other defects occur in timber? Insect attack Click your mouse once to continue
    336. 336. What other defects occur in timber? Shrinkage Click your mouse once to continue
    337. 337. Timber Seasoning
    338. 338. SEASONING Removal of moisture from timber so as to be in equilibrium with moisture in surrounding atmospheric conditions, where timber is likely to be used, is called as seasoning.
    339. 339. Timber Seasoning When timber is first felled it is known as green timber and has a very high moisture content – approx 50% Before it can be used it must be dried If this process is not controlled properly defects can occur that can ruin good timber Aim of seasoning is to dry out the wood to a suitable moisture content of 22% or less
    340. 340. Reasons for Seasoning Seasoning is the controlled process of reducing the moisture content (MC) of the timber so that it is suitable for the environment and intended use. Wood will dry naturally so seasoning helps us to control the process and keep the timber more stable and more useful. Prevents splitting Prevents a lot of fungal and insect attacks It is less likely to distort or warp later After seasoning timber is easier to work with, because it is lighter, harder and stronger.
    341. 341. Influence of Relative Humidity Relative Humidity: the amount of moisture (water vapour) in the air at a given temperature, compared with the maximum amount of moisture the air could hold at the same temperature Wood will continue to shrink or grow (HYDROSCOPIC) to reach equilibrium moisture content. This means that it acclimatises to its surrounding environment. For example if a piece of timber with a moisture content of 12% is placed in a room with a moisture content of 20% the moisture level in the timber will rise until it reaches 20%.
    342. 342. OBJECTIVES OF SEASONING Seasoning improves following properties:  Strength  Durability  Working qualities including polishing, painting, and gluing  Resistance to attack of insects, fungus Proper seasoning reduces tendency to split, shrink and warp. Seasoning reduces weight of timber and is easy to handle. Timber becomes fit to receive preservative treatment
    343. 343. PREPARING TIMBER FOR SEASONING Girdling Coating with thick layers of moisture proof substance such as coal tar, bituminous paint, paraffin wax. Water seasoning
    344. 344. METHODS OF SEASONING SEASONING OF TIMBER Air Seasoning Kiln seasoning Other methods of seasoning- Chemical Seasoning
    345. 345. Air Seasoning
    346. 346. Air Seasoning With this process the timber is roughly sawn to size and stacked using spacers called stickers, with the timber stacked in the open air. Vertical spacing achieved by using timber battens (25mm) of the same species. The piling sticks should be spaced close enough to prevent bowing (600 to 900 mm centres) This allows the free movement of air. The stack should be protected from the direct influence of the elements. The ends of the beams must be painted to prevent splitting.
    347. 347. Air Seasoning Advantages    No expensive equipment needed Small labour cost once stack is made Environmentally friendly- uses little energy Disadvantages    Slow drying rate Large area of space required for a lot of timber Only dries the timber to approximately 20% M.C. so leaving it open to some insect and fungal attacks while it is only suitable for outdoor joinery
    348. 348. Kiln Seasoning There are two main types of kiln used in artificial seasoning  Compartmental Kilns  Progressive Kilns. Both methods rely on the controlled environment to dry out the timber and require the following factors: Forced air circulation by using large fans, blowers, etc. Heat of some form provided by piped steam. Humidity control provided by steam jets. The amount and duration of air, heat and humidity again depends on species, size, quantity, etc. In general, the atmosphere in the kiln at first will be cool and moist. The temperature is gradually increased and the humidity reduced until the required moisture content is achieved.
    349. 349. Compartmental Kilns This kiln is a single enclose container or building, etc. The timber is stacked same manner as air seasoning Whole stack is seasoned using a programme of settings(temperature and humidity) until the whole stack is reduced to the MC required.
    350. 350. Progressive Kilns A progressive kiln has the stack on trolleys that ‘progressively’ travel through a sequence of chambers. Each chamber has varying atmospheres that change the MC of the timber stack as it travels through. Advantages of this system- has a continuous flow of seasoned timber coming off line
    351. 351. Kiln Seasoning Advantages     Quicker due to higher temperatures, ventilation and air circulation Achieve a lower moisture content Defects associated with drying can be controlled Allows more precise rates of drying for various timber species and thickness of boards Disadvantages    Is expensive Requires supervision by a skilled operator Uses a lot of energy
    352. 352. Finding the MC A moisture meter is most commonly used to establish the MC of a particular batch of timber. These meters are usually attached to two probes which send an electrical signal through the wood. Water is a conductor of electricity and therefore – the more water present the higher the conductivity and this can be read from the display. Another method of establishing the MC is to remove random samples from the stack. Each of the samples are placed on a micro scales and their weight recorded. The samples are then placed in an oven or microwave until the moisture has evaporated. The samples are then weighted again and their dry weight recorded. The %MC is obtained by the formulae Wet weight – dry weight X 100 = %MC dry
    353. 353. Finding the MC Find the percentage moisture content of the following sample of wood given the following information; Wet weight = 224g Dry weight = 200g Wet weight – dry weight X 100 = %MC dry weight 224 – 200 X 100 = %MC 200 24 X 100 = %MC 200 0.12 X 100 = %MC
    354. 354. Moisture Content
    355. 355. Seasoning and Shrinkage Seasoning will cause dramatic changes such as increase in strength but also distortion and shrinkage. The greatest amount of shrinkage takes place tangentially along the grain with little loss over the radial direction and along the length of the board. Because of these varying shrinkage rates, tangential boards tend to cup because of the geometry of the annual rings. Some rings are much longer than the others close to the heart.    Therefore there will be more shrinkage at these parts than the others.
    356. 356. Seasoning Defects: Shakes Shakes are separation of the fibres along the grain developed in the standing tree, in felling or in seasoning. They are caused by the development of high internal stresses probably caused by the maturity of the tree. The shake is the result of stress relief and in the first place results in a single longitudinal crack from the heart and through the diameter of the tree. As the stress increases a second relief crack takes form and is shown as a double heart shake. Further cracks are known as star shakes and show the familiar pattern shown.
    358. 358. WOOD PRODUCTS OF TIMBER Veneers Plywood Particle board Fiber boards Batten boards : Block boards and laminated boards
    367. 367. FERROUS METAL AND NON-FERROUS METAL Dr. P. K. Bhuyan NIT Rourkela
    368. 368. FERROUS METAL A metal containing iron as a primary material - Iron - Cast Iron - Steel - Stainless Steel - Wrought Iron
    369. 369. NON-FERROUS METAL A metal containing little or no iron - Aluminum - Bronze - Brass - Copper - Lead
    370. 370. IRON Iron is a metal extracted mainly from the iron ore hematite. It oxidizes readily in air and water to form Fe2O3 and is rarely found as a free element. Iron is believed to be the sixth most abundant element in the universe
    372. 372. Pig iron is the intermediate product of smelting iron ore with coke and resin Cast into pigs in preparation for conversion into cast iron, wrought iron or steel Pig iron has a very high carbon content, typically 3.5 - 4.5%, which makes it very brittle and not useful directly as a material except for limited applications
    373. 373. FERROUS METALS CAST IRON A hard, brittle, nonmalleable iron-based alloy containing 2%-4.5% carbon and 0.5%-3% silicon
    374. 374. FERROUS METALS CAST IRON APPLICATION: - Piping & Fittings - Ornamental Ironwork - Hardware - Base Metal for Porcelain Enameled Plumbing Fixtures - Floor & Wall Brackets for Railings - Circular Stairs - Manhole Cover - Gratings
    375. 375. FERROUS METALS WROUGHT IRON A tough, malleable, readily soft iron that is easily forged & welded. Fatigue & corrosion resistant Commercially pure iron, containing only approximately 0.2% carbon A fibrous material due to the slag inclusions, that gives it a "grain" resembling wood, which is visible when it is etched or bent to the point of failure
    376. 376. FERROUS METALS WROUGHT IRON Literally means “worked iron” APPLICATION: - Piping & Fittings for Plumbing, Heating & Air-conditioning - Ornamental Ironwork
    377. 377. FERROUS METALS GALVANIZED IRON (G.I.) Iron coated with zinc to prevent rust. The process is achieved thru hot-dip galvanizing
    378. 378. FERROUS METALS GALVANIZED IRON APPLICATION: - Metal Decking - Roofing & Accessories - Ceiling Framing - Wall Framing - Piping
    379. 379. FERROUS METALS STEEL Alloys of iron and carbon Carbon content is no more than 2% Alloy elements is composed of phosphorous, sulfur, oxygen, nitrogen, manganese, silicon, aluminum, copper, nickel, etc. Can be wrought, rolled, cast, and welded, but not extruded
    380. 380. FERROUS METALS ALLOY ELEMENTS & IT’S PURPOSE/S: 1. Aluminum for surface hardening 2. Chromium for corrosion resistance 3. Copper for resistance to atmospheric corrosion 4. Manganese in small amounts for hardening; in larger amounts for wear resistance 5. Molybdenum, combined with other alloying metals such as chromium & nickel, to increase corrosion resistance and to raise tensile strength without reducing ductility.
    381. 381. ALLOY ELEMENTS & IT’S PURPOSE/S: 6. Nickel to increase tensile strength without reducing ductility; in high concentrations, to improve corrosion resistance 7. Silicon to strengthen low alloy steels and improve oxidation resistance; in larger amounts to provide hard, brittle castings resistant to corrosive chemicals 8. Sulfur for free machining, especially in mild steels 9. Titanium to prevent intergranular corrosion of stainless steels 10. Tungsten, vanadium, and cobalt for hardness and abrasion resistance
    382. 382. FERROUS METALS Types of Steel: Carbon Steel Alloy Steel - Stainless Steel - HSLA Steel (high-strength low-alloy) - Weathering Steel
    383. 383. FERROUS METALS Carbon Steel Unalloyed steel in which the residual element as carbon, manganese, phosphorus, sulfur and silicon are controlled. Any increase in carbon content increase the strength and hardness but reduces its ductility and weldability.
    384. 384. FERROUS METALS Carbon Steel APPLICATION: - Structural Steel - Concrete Reinforcement - Decking and Panels - Roofing & Accessories - Windows & Doors - Hardware
    385. 385. FERROUS METALS Carbon Steel APPLICATION: - Structural Steel I-beam W-shape S-shape Channels Angles Plates Pipes & Tubing
    386. 386. FERROUS METALS Stainless Steel An alloy steel containing a minimum of 12% chromium & additional nickel, manganese, and molybdenum alloy elements Resistance to heat, oxidation & corrosion Does not stain, corrode or rust as ordinary steel, but not stain-proof
    387. 387. FERROUS METALS Stainless Steel APPLICATION: - Exterior Wall Finishes - Interior Wall Finishes - Railings - Signage - Doors & Windows - Hardware
    388. 388. FERROUS METALS HSLA (High-Strength Low-Alloy) Steel A group of low-carbon steels containing less than 2% alloys in a chemical composition specifically developed for increase strength, ductility, & resistance to corrosion Much stronger & tougher than ordinary carbon steel
    389. 389. FERROUS METALS HSLA Steel APPLICATION: - Reinforcement for Pre-stressed Concrete - High-strength Bolts - Special Structural Steel - Cables for Elevators
    390. 390. FERROUS METALS Weathering Steel A high-strength, low-alloy steel that forms an oxide coating when exposed to rain or moisture in the atmosphere Best-known under the trademark COR-TEN steel
    391. 391. FERROUS METALS Weathering Steel Angel of the North (20x54m), Gateshead, United Kingdom
    392. 392. FERROUS METALS Tools Steel refers to a variety of carbon and alloy steels that are particularly suited to be made into tools Distinctively hard, resistance to abrasion and deformation, and has ability to hold a cutting edge
    393. 393. NNON-FERROUS METALS Aluminum  Soft, non magnetic, ductile and malleable silvery white metal with thermal and electrical conductivity.  Aluminium is the most abundant metal in the Earth's crust, and the third most abundant element therein, after oxygen and silicon. Used as structural framing like the high strength aluminum alloys and secondary building elements such as windows, doors, roofing, flashing, trim and hard wares.
    394. 394. Copper Ductile, malleable and bright reddish brown color with high thermal and electrical conductivity. Posses a “patina” weather reactive surface layer of insoluble green salt which retards corrosion and used to alloy bronze and brass to increase strength and corrosion resistance. Used as electrical wiring, piping and roofing material. Care must be taken in fastening, attaching or supported only by selected brass fittings.
    395. 395. Brass Brass is any alloy of copper and zinc. It has a muted yellow color, somewhat similar to gold. It is relatively resistant to tarnishing, and is often used as decoration and for coins. In antiquity, polished brass was often used as a mirror. Lead Lead is a soft, malleable poor metal, also considered to be one of the heavy metals. Lead has a bluish white color when freshly cut, but tarnishes to a dull grayish color when it is exposed to air and is a shiny chrome silver when melted into a liquid. .
    396. 396. Lead pipe in Roman baths
    397. 397. Tungsten carbide, or tungsten semicarbide, is a chemical compound containing tungsten and carbon, similar to titanium carbide. Tungsten carbide is often simply called carbide.
    398. 398. METAL JOINERY Soldering is a process in which two or more metal items are joined together by melting and flowing a filler metal into the joint, the filler metal having a relatively low melting point. (below 840deg F) Annealing In the cases of copper, steel, and brass this process is performed by substantially heating the material (until glowing) for a while and allowing it to cool slowly. The metal is softened and prepared for further work such as shaping, or forming.
    399. 399. Brazing is a joining process whereby a filler metal or alloy is heated to melting temperature above 450°C (842°F), or, by the traditional definition that has been used in the United States, above 800°F (425°C) and distributed between two or more close-fitting parts by capillary action. Soldering is distinguished from brazing by use of a lower melting-temperature filler metal; it is distinguished from welding by the base metals not being melted during the joining process.
    400. 400. Welding is a fabrication process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material (the weld puddle) that cools to become a strong joint, with pressure sometimes used in conjunction with heat, or by itself, to produce the weld.
    401. 401. A rivet is a mechanical fastener. Before it is installed it consists of a smooth cylindrical shaft with a head on one end. The end opposite the head is called the buck-tail. Blind rivets (also known as pop rivets) The rivet assembly is inserted into a hole drilled through the parts to be joined and a specially designed tool used to draw the mandrel into the rivet.
    402. 402. PROTECTING METALS Alclad is a trademark of Alcoa used as a generic term to describe corrosion resistant Aluminum sheet formed from high-purity aluminum surface layers metallurgically bonded to high strength Aluminum Alloy core material. These sheets commonly used by the aircraft industry Sherardising is a method of galvanizing also called vapor galvanizing. A layer of zinc is applied to the metal target object by heating the object in an airtight container with zinc powder. The temperature that the container reaches does not exceed the melting point of zinc. Another method of sherardisation is to expose the intended objects to vapor from molten zinc using a reducing gas to prevent oxidation.
    403. 403. Geo-synthetics Dr. P. K. Bhuyan NIT Rourkela
    404. 404. What is geo-synthetic? A geo-synthetic has been defined by the “American Society for Testing and Materials (ASTM) Committee on Geosynthetics” as “A planar product manufactured from polymeric material used with soil, rock, earth, or other geotechnical engineering related material as an integral part of a manmade project, structure, or system.”
    405. 405. WOVEN GEOTEXTILE •Uniform and regular interweaving of threads in two directions. •Regular Visible Construction Pattern. •Function: Soil Separation, Reinforcement, Load distribution, Filtration, Drainage •Have high tensile strength and relatively low strain.
    406. 406. NON WOVEN GEOTEXTILE Formed by heat bonding, resin bonding or needle punching. No visible thread pattern. Function: Soil separation, stabilization, load distribution, but not used for reinforcement. They have high strain and stretch considerably under load.
    407. 407. Geo synthetics are classified as follows: 1. Geotextiles 2. Geogrids 3. Geonets 4. Geomembranes 5. Geosynthetic clay liners 6. Geocells/geo web members 7. Geofoam 8. Geocomposites
    408. 408. Geotextiles Geotextiles are defined as “any permeable textile used with foundation soil, rock, earth, or any other geotechnical engineering-related material as an integral part of human-made project, structure, or system”. CHARACTERISTICS Porous and allow flow of water through it. Most used geosynthetics. They may be either woven or non woven Available in rolls of 5-6m wide and 50-150m long. Composed of polymers like polypropylene, high density polyethylene, polyster. Function: Separation, Reinforcement, Filtration, Drainage.
    409. 409. GEOGRIDS •They have open grid like configuration i.e. they have large aperture between individual ribs. •They have Low strain and stretch about 2% under load. •Strength is more that other common geotextiles. •Function: Used exclusively for reinforcement
    410. 410. GEONETS (Geospacers) •Formed by continuous parallel sets of polymeric ribs at preset angles to one another. •Their design function is completely within the in-plane drainage area where they are used to convey all types of liquids. •Though they are used for the drainage function but they have high tensile strength. •Generally used along with one or two geotextile matter one at the top and other at the bottom to prevent soil intrusion .
    411. 411. GEOMEMBRANES •Materials are relatively thin impervious sheets . •Generally made from butyl rubber. •Geomembrane are used more often than geotextiles.
    412. 412. GEOSYNTHETIC CLAY LINERS •This is the mixed position of polymeric materials and natural soil. •Factory fabricated and bentonite clay is sandwitched between 2 geotextile. •Structural integrity is obtained by needle punching. •Function: Containment, As Hydraulic barrier.
    413. 413. GEO CELLS/GEO WEB MEMBERS •Similar to geotextiles or geogrids but have depth. •Formed by High Density Polyethylene sheets. •When opened form honey comb like structure and that contain soil,gravel. •Allow water through it. •USE: In slopes with soft sub-grade erosion control in channels