1. Building Materials

2. BRICKS Clay heated @ < 640 deg C --  only Physical change @ 700 -1100 deg C ---  chemical change, alumina & silica fuse together resulting in compound which is strong & stable  Brick @ > 1300 deg C --  above materials get vitrified (bricks lose shape) Brick size = 20 X 10 X 10 cm. – Nominal, Actual = 19 x 9 x 9 cm. Frog in a brick. Types of bricks (based on manufacturing process) : Wire-cut & Pressed brick Brick classification  General physical requirements  Class I, II, III (color, burnt, shape, water absorption 24 hrs in cold water by weight [20, 22, 25]), Efflorescence. I.S. Classification based on strength  10, 7.5, 5, 3.5. Test for bricks  compressive strength, water absorption [sat. coeff., IRA], Efflorescence,

3. Cement – process of manufacture

11. TriCalcium Silicate 3CaO.SiO 2 ~ C 3 S DiCalcium Silicate 2CaO.SiO 2 ~ C 2 S TriCalcium Aluminate 3CaO.Al 2 O 3 ~ C 3 A TetraCalcium Aluminoferrite 4CaO.Al 2 O 3 .Fe 2 O 3 ~ C 4 AF C 3 S + C 2 S constitute 65-75% by weight of cement and hydrate to form Ca(OH) 2 (~25%) and Calcium Silicate hydrate (~50%) (also called tobermorite gel). C 3 S ---- responsible for initial set and early strength C 2 S ---- increase in strength at ages beyond a week C 3 A ---- responsible for heat of hydration and also contributes slightly to early strength Reducing C 3 A increases sulfate resistance C 4 AF --- reduces clinkering temp. Hydrates rapidly but contributes very less to strength responsible for coloring effects. Type I ---- normal Type II --- moderate sulfate resistant Type III – high early strength Type IV – low heat of hydration Type V --- high sulfate resistant Type I,II,III A --- air-entraining variety

12. Type I ---- general use; where special properties are not required Type II --- general use; moderate sulfate resistance and heat of hydration Type III – when high strength required. Has similarity chemically with Type I but particles are ground finer. typical use cold or underwater structures Type IV – when low heat of hydration is required, typical use massive structures Type V --- when high sulfate resistance is required. Air-entraining materials --- improved resistance to freeze-thaw; scaling caused by chemicals applied for snow/ice removal White cement --- original color, grey comes in due to iron and manganese oxide, used for architectural purpose, curtain walls, tile grout and so on. Types of Ordinary portland cement used in India: grade 33, 43, 53 Fineness – greater cement fineness increases rate at which cement hydrates and accelerates strength development typically during the first week. Soundness – ability of the hardened paste to retain volume after set. (free lime and magnesia responsible for lack of soundness). More sound less shrinkage. Consistency – ability to flow. Depends on water-cement ratio. Setting time – affected by gypsum content, cement fineness, w/c ratio, admixtures Compressive strength – measured by 2 inch mortar cube. Compound composition and fineness of cement affects it. Heat of hydration – heat generated when cement and water react. Increase in w/c ratio, fineness of cement, curing temp increases heat of hydration. Specific gravity --- 3.15

13. Fineness measurement of cement (sq. cm per kg. of cement) Blaine’s air permeability test Wagner’s turbidimeter

14. Conduction calorimeter – Heat of hydration

15. Materials to supplement cement Contributes to the properties of hardened concrete through hydraulic or pozzolanic activity or both Pozzolan :- Sliciceous or aluminosiliceous material that in finely divided form and presence of moisture, chemically reacts with calcium hydroxide released by hydration of portland cement to form calcium silicate hydrate and other cementitious material Fly Ash Byproduct of combustion of pulverized coal in electric power generating plants During combustion, coal’s mineral impurities (clay, feldspar, quartz, shale) fuse in suspension and are carried away from combustion chamber by exhaust gas. The fused Materials cool and solidifies into spherical glassy particles. Silica, alumina, iron, calcium 1.9-2.8

16. Granulated blast-furnace slag Non-metallic hydraulic cement consisting essentially of silicates and aluminosilicates of calcium developed in a molten condition simultaneously with iron in blast-furnace. Molten slag rapidly chilled by quenching in water  glassy sandlike granulated material Silica Fume Byproduct obtained as a result of reduction of high purity quartz with coal in an electric-arc furnace in the manufacture of silicon or ferro-silicon alloy

20. Particle size distribution graph of fine aggregates Min. value Max value Sample

25. Concrete Concrete is itself a composite material. It is composed of aggregate and is chemically bound together by hydrated Portland cement . Aggregate = Sand + Gravel. Maximum size of gravel: Building construction = ¾ of an inch Bridge = 1 to 1 ½ inches Concrete = Sand + Gravel + Water + Cement

30. Curing of fresh concrete to make hardened concrete Concrete curing should be done at 70 deg F for at least 7 days and kept continuously moist after initial set. (ACI 5.11). It gains 75% of its final strength In roughly 28 days. Moisture and Temp. => Influences process of concrete curing

34. Air entrained concrete Produced by using 1) air entraining cement or 2) air entraining agent. Air entraining agent enhances the incorporation of bubbles of various sizes by lowering surface tension of mixing water. Effects of increase in entrained air on concrete properties: Bleeding --- significantly reduced Bond to steel ---- reduced compressive strength --- reduced approx 2-6% per % point increase in air flexural strength --- reduced approx 2-4% per % point increase in air freeze-thaw resistance --- significantly improved modulus of elasticity --- decreases slump ---- increases sulfate resistance --- significantly improved unit weight --- decreases water demand --- decreases for same slump workability --- increases Factors affecting air-content: cement content, fineness increase --- decreases air content high alkali cements entrain more air than low alkali cements smaller aggregate size --- air content increases (no change beyond 1.5 in) more amount of fine aggregates ---- increases air content

35. Factors affecting air content mixing water increase ---- generates air bubbles --- more air content increase in vibration --- reduction in air content for constant amount of air-entraining admixture --- increase in slump increase air content up to about 6-7 in. concrete temp increase ---- less air entrained

36. Concrete admixtures Ingredients in concrete other than portland cement, water and aggregates which are added to the mixture immediately before or during mixing. Types of admixtures: Air entraining admixtures water reducing admixtures --- water/cement ratio reduced --- strength increase (plasticizer(8-15%), super-plasticizer (15-30%)) Retarding admixture --- retard rate of setting of concrete --- control heat of hydration --- hot weather application Accelerating admixtures --- accelerate strength development at early stage ---- cold weather applications and underwater applications Waterproofing admixtures --- cause capillary contraction resulting in impervious concrete (Aquaproof, cico, impermo) Mineral admixtures cementitous material --- granulated blast furnace slag, hydrated lime. pozzolonic material --- siliceous or aluminosiliceous material, in presence of water reacts with CaOH2 to form compound possessing cementitious properties -- fly ash, silica fume nominally inert materials --- raw quartz, dolomite, limestone

37. Lime Quicklime Hydrated lime / slaked lime Carbonation of hydrated lime results in calcium carbonate  cementing properties Sand added to lime  increase in bulk (leads to economy) to make mortar porous, so that air can circulate resulting in better carbonation Eminently hydraulic lime : structural work such as arch, dome Semi-hydraulic lime : constructing masonry Fat lime & Dolomite lime: finishing coat in plastering, white wash Kankar lime : masonry lime Siliceous Dolomite lime : undercoat and finishing coat of plaster Fibers in concrete

38. Mortar and Plaster Primary property : Bonding agent under different loading condition Masonry mortar Strength of mortar depends on strength of blocks it is binding. Should not be too off. Cement-sand mix ratio (Cement mortar) Damp-proof course -- 1:2 General brickwork -- 1:6 Stone masonry – 1:6 Brickwork below ground – 1:3 – 1:4 Cement plaster Brickwork plaster (inside + outside) – 1:5 R.C. Plaster – 1:4

41. Weathering Rotting

42. Seasoning of wood: Heat treatment as well as chemical treatment of wood to prevent its deterioration and restore strength Chemicals used include waterborne and oil-borne creosote.

44. Failure in timber structures shear Flexure Compression

45. Industrial timber products : Plywood Particle board (chipboard) Hardboard Fiberboard Blockboard Glulam

46. Cast Iron and Steel

47. Bitumen, Asphalt & Tar Tar – dark colored product obtained from destructive distillation of organic substances like coal, wood and bituminious shales. Asphalt: A black or dark brown non-crystalline solid or viscous material, composed principally of high molecular weight hydrocarbons, having adhesive properties, derived from petroleum either by natural or refinery processes and substantially soluble in carbon disulphide. Asphalt = bitumen + inert mineral matter Bitumen is the binding material in asphalt

49. Types of Bitumen: Straight run Bitumen – bitumen distilled to a definite viscosity of penetration such that no further treatment like heating is required Blown bitumen – Liquid bitumen + pass air under pressure to remove volatile compoun Penetration grade – basic form, has to be heated before application Cutback bitumen – bitumen + petroleum distillates Bitumen Emulsion – product in liquid form formed in aqueous medium and stabilizing `agents Plastic Bitumen – bitumen thinner + suitable filler  plastic form Cutbacks – bituminious material in solvent Residual bitumen – solid substance at normal temp, obtd. as residue during distillation of high resin petoleum Modified bitumen – bitumen combined with plastic

50. Fiber reinforced polymers

51. Geosynthetics

52. Crumb rubber

53. Plastics

54. Foams and Honeycomb materials

55. Glass

56. Composites