![PETROLEUM REFINING PROCESS
2. Destructive Distillation
- involves the application of intense heat [temperature
as high as 1100oF (593oC)] and high pressure [as
high as 735psi (5MPa)], which cause chemical
changes in material](https://image.slidesharecdn.com/bituminousmaterialsandmixtures-230225130731-2dda6a76/85/Bituminous-Materials-and-Mixtures-ppt-14-320.jpg)
Bituminous Materials and Mixtures.ppt
- 2. SPECIFIC OBJECTIVES: define bitumen be familiarize and understand the bituminous materials and mixtures At the end of the lesson, the student should be able to:
- 3. BITUMINOUS MATERIALS AND MIXTURES BITUMEN - road-surfacing material: a mixture of hydrocarbons derived from petroleum and found in substances such as asphalt and tar that are used for road surfacing and roofing BITUMENS
- 4. BITUMINOUS MATERIALS Bitumen Asphalt Tars Pitches Natural deposit Petroleum Asphalt Native Asphalt Rock Asphalt Asphalt Cement (solid or semisolid) Cutback Asphalt (liquid) Emulsified Asphalt (liquid) Blown Asphalt (semisolid) Slow Curing Medium Curing Rapid Curing
- 5. BITUMINOUS MATERIALS AND MIXTURES ASPHALT - semisolid bituminous substance: cementitious materials in which the predominant constituent materials are bitumens
- 6. TARS and PITCHES Tar - thick black liquid: a thick black liquid obtained through the destructive distillation of an organic substance such as wood or coal *produced by the destructive distillation of bituminous coal called bituminous coal tar which is most commonly used tar in pavement construction COAL TAR
- 7. TARS and PITCHES Crude tar - contains a large amount of water as well as some fuel oils - viscous liquid produced at the end of the distillation process Pitches -substance obtained from tar: a dark sticky substance obtained from tar and used in the building trade, especially for waterproofing roofs -liquefied gradually when heated
- 8. TYPES OF NATURAL DEPOSIT ASPHALTS 1. Natural Rock Asphalts 2. Native Asphalts (Lake Asphalts)
- 9. TYPES OF ASPHALTS 1. Natural Rock Asphalts - found in many parts of the world as deposits of sandstones or limestone filled with asphalts through geologic process
- 10. TYPES OF ASPHALTS 2. Native Asphalts (lake asphalts) - bitumens mixed with water, fine siliceous silt, clay and organic mater (found in Lake Trinidad)
- 11. PETROLEUM ASPHALTS Refining and distillation of petroleum results in various types of asphalt or asphaltic material Distillation -process in which various fractions (products) are separated out of the crude by raising its temperature in stages
- 12. PETROLEUM REFINING PROCESS 1. Fractional Distillation 2. Destructive Distillation (cracking)
- 13. PETROLEUM REFINING PROCESS 1. Fractional Distillation - involves the separation of crude oil into various materials without significant changes in the chemical composition of each materials
- 14. PETROLEUM REFINING PROCESS 2. Destructive Distillation - involves the application of intense heat [temperature as high as 1100oF (593oC)] and high pressure [as high as 735psi (5MPa)], which cause chemical changes in material
- 15. Petroleum asphalts are classified into four types 1. Asphalt Cements 2. Cutback Asphalts 3. Emulsified Asphalts 4. Air-Blown Asphalts Cutback Asphalts are further divided into three types • Slow Curing • Medium Curing • Rapid Curing
- 16. Asphalt Cement - (also called paving asphalt) - very sticky and highly viscous especially prepared with the quality and consistency required in the manufacture of asphalt pavements (hot mix pavements)
- 17. Cutback Asphalt - asphalt cement that is liquefied by blending with petroleum solvent (called diluents)
- 18. CURING UNDER CUTBACK ASPHALT 1. Slow Curing 2. Medium Curing 3. Rapid Curing
- 19. CURING UNDER CUTBACK ASPHALT 1. Slow Curing - asphalt cement blended with oils of low volatility, such as diesel oil. - its viscosity value is low and hardens very slowly
- 20. CURING UNDER CUTBACK ASPHALT 2. Medium Curing - obtained by blending asphalt cement with kerosene-type diluents of medium volatility
- 21. CURING UNDER CUTBACK ASPHALT 3. Rapid Curing - asphalt cement-blended with naphtha or gasoline-type diluents of high volatility
- 22. DISADVANTAGES OF CUTBACK ASPHALTS • The volatile distillate may evaporate in the air and add to air pollution • The distillate in the cutback asphalt poses and toxicity hazards.
- 23. EMULSIFIED AND BLOWN ASPHALT Emulsified Asphalt - composed of asphalt cement and water that contains a small amount of an emulsifying agent (soaps, water-soluble chemicals and fine clay)
- 24. ADVANTAGES OF EMULSIFIED ASPHALTS • It can be applied during damp weather and with aggregates that are cold or hot • Also eliminates the use of fuel required to heat and dry the aggregates in the asphalt cement mixtures
- 25. DISADVANTAGE OF EMULSIFIED ASPHALTS • Because the asphalt is suspended in water, it is susceptible to being washed off a road surface by rainwater if not sufficiently cured
- 26. EMULSIFIED AND BLOWN ASPHALT Blown Asphalt - obtained by blowing air through the semisolid residue obtained during the later stages of the distillation process
- 27. PROPERTIES OF ASPHALT • Adhesion • Consistency • Specific Gravity • Durability • Rate of Curing • Ductility • Aging and Hardening • Resistance to reaction with water • Temperature Susceptibility
- 28. PROPERTIES OF ASPHALT Specific Gravity - normally measured using pycnometer Specific Gravity of Asphalt - is the ratio of the mass of the given volume of the material at 77oF (25oC) or at 60oF (15.6oC) to the mass of an equal volume of water at the same temperature.
- 29. PROPERTIES OF ASPHALT Specific Gravity of Petroleum Asphalt - value close to unity (0.95-1.05) Specific Gravity of Road Tars - varies between 1.08-1.24
- 30. PROPERTIES OF ASPHALT Knowledge of specific gravity is essential: • to determine the percentage of voids in a compacted material • its measurement is required to convert the volume measurement of asphalt to the units of mass.
- 31. PROPERTIES OF ASPHALT Durability - the property that permits a pavement material to withstand the detrimental effects of moisture, air, and temperature Oxidation - chemical reaction that takes place when asphalt is exposed to the oxygen in air
- 32. PROPERTIES OF ASPHALT Volatilization - process by which lighter hydrocarbons from the asphalts are evaporated - affects by the temperature.
- 33. PROPERTIES OF ASPHALT RATE OF CURING Curing -the process of evaporation of solvents from cutback asphalts, and the attendant thickening of the material -the change in consistency of an asphaltic material due to the progressive loss of diluents by evaporation
- 34. RATE OF CURING PROPERTIES OF ASPHALT - is the time required for a cutback asphalt to harden (from its original liquid consistency) and develop a consistency that is satisfactory for the function as a binder in pavements is an important property of cutback asphalt
- 35. PROPERTIES OF ASPHALT RATE OF CURING
- 36. PROPERTIES OF ASPHALT In emulsified asphalts - the rate of evaporation of water depends on the weather conditions, such as humidity and temperature RATE OF CURING *with favorable weather conditions, the water evaporates quickly and curing progresses rapidly
- 37. PROPERTIES OF ASPHALT Age Hardening - process of natural hardening of asphalt Rate of Hardening - decreases with time and is insignificant beyond 1 year *this process happens even when oxidation and volatilization are prevented from occurring
- 38. PROPERTIES OF ASPHALT Resistance to Action of Water *the asphalt materials for pavements should be able to withstand the effects of water *complete drying of the aggregate particles prior to mixing improves pavement performance
- 39. PROPERTIES OF ASPHALT Ductility *ductility material with sufficient bonding characteristics, such as asphalts and tars, exhibit adhesive and cohesive properties
- 40. PROPERTIES OF ASPHALT Temperature Susceptibility Asphalt A Asphalt B (A & B are of identical viscosity grade T1 Temperature susceptibility of asphalts
- 41. PROPERTIES OF ASPHALT Hardening and Aging Original Aged (Rolling thin film oven test) Hardening of asphalt after exposure to high temperatures
- 42. ASPHALT AGGREGATES Asphalt cements are graded according to four different systems: • Viscosity grading system • Viscosity after-aging grading system • Penetration grading system • Performance-based grading system
- 43. PERFORMANCE-BASED GRADING The research studies carried out in the program concluded that asphalt pavements often fails or crack due to three major reasons: 1. Pavement Deformations or rutting at high temperatures, as asphalt softens and the binder loses elasticity
- 44. three major reasons of cracking of asphalt pavements 2. Fatigue resulting from high pavement loads or aging 3. Low-temperature cracks, as asphalt becomes brittle and the pavement shrinks in cold weather
- 45. CUTBACK ASPHALT GRADES Cutback asphalts - are graded based on their kinematic viscosity at 140oF (60oC) in centistoke
- 46. ASPHALT CONCRETE - used for construction of asphalt pavement, in which is also called flexible concrete, due to its ability to conform to settlement of the foundation
- 47. • Hot-Mixed Asphalt >or hot-laid bituminous mixtures • Cold-Mixed Asphalt >or cold-laid bituminous mixtures TYPES OF ASPHALT CONCRETE
- 48. TYPES OF ASPHALT CONCRETE Hot-Mixed, hot-laid bituminous mixture - fine aggregate, or a mixture of coarse and fine aggregate, with or without mineral filter, uniformly mixed with asphalt cement, tar, or emulsified asphalts
- 49. TYPES OF ASPHALT CONCRETE Cold-Mixed, cold-laid bituminous mixture - is coarse aggregate, fine aggregate, or a mixture of coarse and fine aggregates, with or without filter, uniformly mixed with liquid bitumen and laid at or near ambient temperature
- 50. TYPES OF ASPHALT CONCRETE Asphalt Rubber - or crumb rubber - which is recycled product from old tires is used in hot-mixed asphalt pavements to improve the binding property of aggregates
- 51. TYPES OF ASPHALT CONCRETE Glasphalt - is the term used to describe asphalt that is party replaced by glass
- 52. ASPHALT PAVEMENT Asphalt (flexible) pavement - has sufficiently bending resistance to maintain intimate contact with the underlying structure or base, yet has the required stability to support traffic loads
- 53. ASPHALT PAVEMENT
- 54. ELEMENTS OF FLEXIBLE PAVEMENTS • Subgrade • Subbase Course • Base Course • Surface Course
- 55. ELEMENTS OF FLEXIBLE PAVEMENTS Subgrade - also called prepares roadbed - consist of natural or imported soil, such as in an embankment, improved by stabilization
- 56. ELEMENTS OF FLEXIBLE PAVEMENTS Subbase - is a layer between the subgrade and the base course - made from minerals generally superior to that of subgrade
- 57. ELEMENTS OF FLEXIBLE PAVEMENTS Base Course - or base layer, lies directly beneath the wearing surface - it can also be constructed as an asphalt concrete base (asphalt base course) or as an untreated aggregate base
- 58. The base layer is generally identified by the type of material used: • Aggregate • Asphalt cement • Asphalt-treated permeable • Cement treated • Cement-treated permeable • Lean concrete
- 59. The base layer is generally identified by the type of material used: Aggregate
- 60. The base layer is generally identified by the type of material used: Asphalt Cement
- 61. The base layer is generally identified by the type of material used: Asphalt-treated Permeable
- 62. The base layer is generally identified by the type of material used: Cement treated
- 63. The base layer is generally identified by the type of material used: Cement-treated Permeable
- 64. The base layer is generally identified by the type of material used: Lean Concrete
- 65. ADVANTAGES OF USING ASPHALT CONCRETE AS CONSTRUCTION MATERIAL Economical Durable Safe Recyclable Quick and easy to repair
- 66. DISADVANTAGES OF USING ASPHALT CONCRETE AS CONSTRUCTION MATERIAL More maintenance Prone to crack Substantial training for installers Can cause pollution Require heavy equipment
- 67. ASPHALT LABORATORY TESTS Ductility Test Extraction Test Penetration Test Specific Gravity Test Marshal Stability Test
- 68. ASPHALT LABORATORY TESTS Ductility Test The ductility of a bituminous material is measured by the distance in cm to which it will elongate before breaking when a standard briquette specimen of the material is pulled apart at a specified speed and a specified temperature.
- 69. ASPHALT LABORATORY TESTS Extraction Test The extraction test involves adding a solvent to the asphalt mixture to dissolve the asphalt cement. Then the asphalt concrete and solvent are centrifuged to assure that all the asphalt is dissolved leaving a clean aggregate.
- 70. ASPHALT LABORATORY TESTS Penetration Test Penetration value test on bitumen is a measure of hardness or consistency of bituminous material. ... Penetration value is the vertical distance traversed or penetrated by the point of a standard needle into the bituminous material under specific conditions of load, time and temperature.
- 71. ASPHALT LABORATORY TESTS Specific Gravity Test Because the specific gravity of asphalt binders change with temperature, specific gravity tests are useful in making volume corrections based on temperature.
- 72. ASPHALT LABORATORY TESTS Marshall Stability Test The marshall stability of mix is defined as a maximum load carried by a compacted specimen at a standard test temperature of 60ºC. The flow value is deformation the marshall test specimen under goes during the loading up to the maximum load, 0.25 mm units.