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Material Technology

Material Technology. Asphalt . Asphalts – origin and manufacturer. Binding agent produced from coal (coal tars, pitches, etc.,) Produced from crude oil Asphalt Cement: a dark brown or black colored bituminous materials used for hotmix asphalt

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Material Technology

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  1. Material Technology Asphalt

  2. Asphalts – origin and manufacturer • Binding agent produced from coal (coal tars, pitches, etc.,) • Produced from crude oil • Asphalt Cement: a dark brown or black colored bituminous materials used for hotmix asphalt • Asphalt is viscous materials, means that exhibits both viscous and elastic behaviour

  3. Asphalts – origin and manufacturer • Asphalt (Europe & North America) • It is means a mixture of bitumen and mineral aggregates, such as rolled asphalt, mastic asphalt, gussaphalt) • Asphalt (North America) is bitumen

  4. Production of Petroleum Asphalt Asphaltic Base Crude Oil Basic Type of Petroleum Paraffin Base Crude Oil Mixed Base Crude Oil

  5. Distillation Process • Distillation of petroleum is Fractional • Produce by Physical Process

  6. Production of Petroleum Asphalt STRAIGHT RUN PROCESS • Overheating • Chemical changes (Distillation process – under controlled) TWO STEPS OF PRODUCT PROCESS • Pumping process (crude oil to tube heater) • Distillation process

  7. atmospheric pressure Series of traps to catch distillates Naphtha To further distilling and cracking processes Gasoline Kerosene Decreasing temperature Diesel Oil From storage 5000F high pressure Hot topped crude (atmospheric residuum) Schematic Cross Section of distillate trap Level control of distillate Still tube heater Path of Gas Atmospheric pressure distillation

  8. Partial Vacuum Series of traps to catch distillates Light vacuum distillate Non volatile oils Hot top crude 5000F high pressure Heavy vacuum distillate steam Asphalt cement Still tube heater Vacuum steam distillation

  9. The fractions of Petroleum

  10. Chemical composition • Structure: • High molecular-weight hydrocarbon • CnH2+bXd (X = sulfur, Ni, O, trace-metal) • (n = 25 – 150 atoms) • Composition(%): • Carbon 80 – 87 Nitrogen 0 - 1 • Nitrogen 9 -11 Sulfur 0.5 – 7 • Oxygen 2 – 8 Trace metal 0 – 0.5 • Affecting: boiling point, solubility, viscosity

  11. Molecular composition • ALIPHATIC: Paraffin – carbon atom linked in straight or brain chains • NAPTHENIC: Carbon atom are linked in simple-complex (condensed) saturated rings • AROMATIC: Carbon atom are linked in especially stable benzene rings

  12. Physical structure ASPHALTHENES 100% OILS 100% 100% RESINS

  13. Constituent of A. C.

  14. Properties of Asphalt: Function of: (Temperature; Chemical Nature; Volume of Constituent)

  15. LIQUID ASPHALT • Cutback asphalt • Cutback Asphalt are produced by blending as asphalt cement with a hydrocarbon solvent • Classified as based on curing phase: • RC = rapid curing (asphalt mixed with gasoline); • MC = medium curing; (asphalt mixed with kerosene) • SC = slow curing (asphalt mixed with diesel oil) • Grade range estimated based on viscosity) and types: • RC range: RC 70 (70-100); RC 250 (200-300); RC 800 (800-1000); RC 3000 (3000-4000) • MC range: MC 30 (30-40); MC 70 (70-140); MC 250 (200-500); MC 3000 (2000-6000) • SC range: SC 70 (70-140); SC 250 (250-500); SC 800 (800-1600); MC 3000 (2000-6000)

  16. Cutback ASPHALT

  17. LIQUID ASPHALT • Emulsified asphalt • Emulsified Asphalt are produced by breaking asphalt cement into very fine droplets or particles and dispersing these in a mixture of water and a surface active emulsifying agent. • Two type of emulsified asphalt: anionic and cationic • Classified based on setting time: • Anionic Emulsified Asphalt: • RS = rapid setting: RS1; RS2 • MS = medium settingMS2 • SC= slow settingSS1; SS2 • Cationic Emulsifed Asphalt: • RS ; RS-2K; RS-3K • MS ; SM-K; CM; K • SS ; SS –K; SS-Kk

  18. Specification for Asphalt Cement Source: ASTM D946 Standard Specification for Penetration Graded Asphalt Cement for use in Pavement Construction

  19. Method of Testing • Penetration • Specific Gravity • Ductility • Viscosity • Flash Point • Softening Point

  20. Penetration • To measure the hardness or softness of a bitumen material under a given set of condition • The consistency test used to designate grade of asphalt cement • Results (common used): Pen 40 - 50 60 - 70 85 - 100 120 - 150 200 - 300 Test Reference: ASTM D5

  21. D 100 gram Load of 100 gram is applied for 5 second at 770F or 250 C D = penetration in units of 0.1 mm Penetration Asphalt Cement 770F or 250 C

  22. (C – A) (C – A) – (D – C) Specific Gravity Reference: ASTM D70 (specific gravity and density of semi-solid bituminous materials) Procedures: • The sample is heated until it can be poured • The material is placed in a pycnometer • The asphalt volume is determined by taking the difference between total vol of the bottle and the volume of water required to complete the filling • Specific Gravity = • A=weight of pycnometer B = weight of pycnometer filled w water C= weight of pycnometer partially filled with asphalt D= weight of pycnometer plus asphalt plus water

  23. Ductility Reference: ASTM D113 (Ductility of Bituminous Materials) Procedures: • The two ends of briquette specimen are pulled apart at a specified speed and temperature in a liquid medium • The ductility is measured by the distance to which it will elongated before breaking. • Temperature test is 250C, elongation rate is 5 cm/minute • Total elongation is average at max 200 cm • The objective of test are: -adhesiveness; and –elasticity of asphalt

  24. Ductility Machine Gaya Tarik Gaya Tarik Media Cairan – alkohol atau cairan garam Benang Aspal Klem

  25. Panjang Sampel P kg P kg P kg P kg Panjang Sampel + pasca penarikan Daerah Putus Ductility Test Result

  26. Ductility Affects • Adhession: • The ability to stick to aggregate particles in the pavement • Refer to the molecular force that exists in the area of contact between unlike bodies • Cohesion: • The ability to hold the particles firmly in place • The molecular force that acts to unite the particles (cohesive organization) • Ductile material has an excellent adhesive and cohesive properties

  27. Softening Point • Transition between solid to liquid • The higher the softening point, the less the temperature susceptibility

  28. Softening Point Reference: ASTM D 36 – 66T (test for softening point of Asphalts and Tar Pitches RING and BALL method • Heat is applied to raise temperature from 410 F at a rate of 90 F/min • The temperature is read from a thermometer at the instant the asphalt sample touches the bottom of a reference plate • The temperature different between two balls do not exceed than 0.50 F

  29. asphalt asphalt heat Softening Point - temperature

  30. Durability • Defined as the property that permits a pavement materials to withstand the detrimental effects of moisture, air and temperature. • Affected by i.e., mix design; properties of aggregate; properties of asphalt; and workmanships. • Method of test: -the thin film oven (ASTM D 1754); the rolling thin-film oven test (ASTM D 2872)

  31. Durability • Oxidation: • The chemical reaction which takes place when asphalt is exposed to the oxygen in air • It affect the hydrogen in the asphalt combines with oxygen in the air and is removed as water molecules. • The loss of hydrogen increases the carbon/hydrogen ration, increases the hardness of materials and loss of ductility and adhesion.

  32. Durability • Volatilization • Affected by temperature • The process by which lighter hydrocarbons evaporates from the asphalt • Causes loss of plasticity in asphalt • The rate of oxidation and volatilization almost double for each 100C rise in temperature

  33. Solubility Test reference ASTM D 4-52 • To determine the amount of cementing agencies present • This is useful for native asphalt • To determine the amount of bitumen insoluble in naptha

  34. Flash Point • The flash point test are used to determine the temperature to which asphalt materials may be safely heated. • The flash point is the heating temperature at which the vapor pressure is high enough to give off sufficient hydrocarbon vapors to form an explosive mixture with air when contacted with open flame.

  35. Asphalt sample thermometer gas heat Flash Point – temperature

  36. Temperature Susceptibility • Asphalt will become harder (more viscous) with decrease in temperature and softer (less viscous) with increase in temperature.

  37. A and B are of identical viscosity grade Asphalt B Viscosity Asphalt A Temperature

  38. NATURAL ASPHALT

  39. Types of Asphalts –binders – origin and manufacturer • Lake Asphalts • Rock Asphalt • TAR • Bitumen

  40. Lake Asphalts • Known as NATURAL Asphalt • Found in well defined surface deposits, such as located in Trinidad (discover by Sir Walter Raleigh – 1595) • Found in Venezuela, called as Bermuda Asphalt

  41. Lake Asphalts Trinidad Lake Asphalt • The lake is approximately 35 hectare and 90 meter deep, containing about 15 million ton of material. • Assume as originated as a surface seepage of a viscous bitumen in lake Miocene times. Lowering of the earth’s surface led to an incursion of the sea and as a result deposited silt and clay over the bitumen. • Part of silt and clay penetrated the bitumen, forming a plastic mixture of silt, clay, water and bitumen. Subsequently the land was elevated above sea level, lateral pressure deforming the material into its present shape of a pseudo-laccolite. • Erosion remove the silt and clay covering exposing the surface of the lake.

  42. Lake Asphalts the composition Trinidad Asphalt • 30 percent water and gas • 40 percent asphalt (soluble in carbon disulfide) • 30 percent mineral matter

  43. Lake Asphalts the characteristics Crude Trinidad Asphalt • Penetration at 770 F is range 1,5 – 4,0 • Ductility at 770 F is 3 • Solubility in carbon disulfide is 57 – 57 percent

  44. Lake Asphalts Bermuda Lake Asphalt • The lake is approximately 445 hectare and 0,5 – 2,4 meter deep • Containing the largest deposits (volume still unknown). • Exuded ages ago through faults in the underlying rock strata • To remove the asphalts a dam is built of slag and waste and the water is pumped out, asphalt is dig out by hand and loaded into small cars. • The water is not thoroughly mixed with the asphalt.

  45. Lake Asphalts the composition Bermuda Asphalt • 60 percent asphalt (soluble in carbon disulfide) • 3 percent insoluble non-mineral matter • 2 percent mineral matter • 30 percent water

  46. Lake Asphalts the characteristics Crude Bermuda Asphalt • Penetration at 770 F, is range 20 – 30 • Ductility at 770 F is 11 • Non-uniformity is Nature • Solubility in carbon disulfide is 92 – 97 percent

  47. Rock Asphalt origin and manufacturer • Formed by the impregnation of calcareous rocks (limestone; sandstones) with seepage of natural bitumen. • The product can be mined (quarried) and contain approx. 12% mass bitumen • Asphalt content on the rock vary to a approx. 20% • Used as a mixture of the asphalt and the rock that contains it

  48. Rock Asphalt origin and manufacturer The advantages: • It produces a non skid surface (often used as an anti-skid surfacing material) • It is uniform in quality • It is uniform in appearance

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