VALUE ADDED BITUMEN

1
VALUE ADDED BITUMEN
2

• Mankind is driven forward by dim apprehensions
  of things too obscure for its existing language.
• Zen and the Art
  of Motorcycle
• Maintenance,
• 
  Robert M. Pirsig

3
What is Bitumen?

• A viscous liquid or a solid, consisting
  essentially of Hydrocarbons and their
  derivatives, which is soluble in
  Trichloroethylene and is substantially
  non-volatile and softens gradually when heated.
  It is Black or Brown in colour and posses water
  proofing adhesive properties. It is obtained by
  refining processes from Crude Petroleum.

4
B I T U M E N
A VISCO - ELASTIC MATERIAL
5
Engineering Properties of Bitumen

• Bitumen is a visco-elastic material its
  deformation under stress is a function of both
  temperature loading time
• At higher temperature /or longer loading time
• Behave as viscous liquids
• At low temperature /or short loading time
• Behave as elastic solids
• The intermediate range of temperatures, more
  typical of the conditions in service, result in
  visco-elastic behaviour.

6
The Stiffness Concept

• In solids
• E s
• e
• where E Elastic modulus
• s Stress
• e Strain

7
The Stiffness Concept

• St,T s
• et,T
• Where St,T Stiffness modulus at
  specific time t
  Temp. T.
• s Stress
• et,T Strain at specific time t
  temp. T.

8
COMPOSITION

• B I T U M E N

9
Elemental Analysis

• Carbon 82 - 88
• Hydrogen 8 - 11
• Sulphur 0 - 6
• Oxygen 0 - 1.5
• Nitrogen 0 - 1

10
Chemical Composition

• Bitumen
• Asphaltenes (5 to 25 wt.)
• Maltenes
• Saturates (5 to 20 wt.)
• Aromatics (40 to 65 wt.)
• Resins (10 to 20 wt.)

11
Elemental Analysis

• Elemental composition depends on
• origin of crude
• processes used in refinery
• Elemental composition
• Extremely complex with the number of molecules
  with different chemical structures being very
  large
• Not feasible to attempt a complete analysis
• Elemental composition provides little
  information of the types of molecular structure

12
Properties

• of
• BITUMEN

13
Properties of Bitumen

• Characteristics 80/100 60/70 30/40
• Specific gravity at 27OC 0.99 0.99
  0.99
• Softening Point OC 35 to 50 40
  to 55 50 to 65
• Penetration at 25OC, 100gm, 80 to 100 60
  to 70 30 to 40
• 5 secs., 1/10 mm
• Ductility at 27OC, in cm min. 75 75 50

14
SIGNIFICANCE OF TESTS

• Penetration Test
• Indicates consistence
• Softening Point
• Indicates melting temperature
• Loss on heating / thin film oven test
• Hardening on road
• Ductility Test
• Affinity for aggregates
• Solubility in Trichloroethelene
• Indicates purity of Bitumen

15
Penetration

• Travel in dmm of a specified needle under 100 g
  wt. for 5 secs into Bitumen at 25OC
• Denotes consistency

16
Softening Point

• 3.5 g steel ball placed on Bitumen sample in
  Brass ring
• Bath temp. raised at 5OC per minute

17
DUCTILITY

• Indicates the extent to which a sample can be
  stretched before breaking.
• Length in cm. at breaking point is ductility

18
FLASH POINT

• Used to measure temperature to which a sample
  bitumen may be safely heated
• The flash point is the temperature reached when
  the vapour causes an instantaneous flash

19
Value Added Bitumen

• Cutback
• Bitumen Emulsions
• Modified Bitumen
• Modified Bitumen Emulsions
• Multigrade Bitumen

20
CUTBACK

• BITUMEN

21
CUTBACK BITUMEN

• Manufactured by blending solvents like Kerosene
  with Bitumen
• Free flowing liquid at ambient temperature
• Used for tack coat and prime coat applications.

22
Types of Cutbacks

• Rapid Curing (RC 70, 250, 800, 3000)
• For aggregate passing 2.36 mm sieve
• Medium Curing (MC 70, 250, 800, 3000)
• For less than 20 aggregate passing 2.36 sieve
• Slow Curing (SC 70, 250, 800, 3000)
• For more than 20 aggregate passing 2.36 sieve

23
BITUMEN

• EMULSIONS

24
Bitumen Emulsion

• Chocolate brown free flowing liquid at ambient
  temperature
• Stable dispersion of fine globules of bitumen in
  continuous water phase
• Dispersion is obtained by processing bitumen and
  water under controlled conditions through a
  colloidal mill with selected additives.

25
Types of Bitumen Emulsion

• Cationic Bitumen Emulsion Anionic Bitumen
  Emulsion.
• Anionic not used for road work as aggregates are
  generally siliceous.
• Cationic Bitumen Emulsions used in roadwork
  worldwide.

26
Emulsion Ingredients

• Bitumen (80/100)
• Emulsifier
• Chemicals / additives
• Water

27
Emulsification

• Bitumen milled into fine particles held in
  molecular spaces of water
• Use of correct emulsifier / chemicals facilitate
  proper emulsification

28
Breaking

• Electrostatic attraction causes breaking of
  emulsion
• Bitumen ve charge
• Aggregate -ve charge
• Result excellent bonding / antistripping
  between bitumen aggregate

29
Types of Cationic Emulsions

• Slow Setting
• Medium Setting
• Rapid Setting

30
MODIFIED BITUMEN

• Binder of the future

31
Why Modified Bitumen?

• Demands on Road increasing every year
• Increasing Number of Vehicles
• Increasing Axle Load
• Desire to maintain higher serviceability level
• Higher fatigue resistance
• Higher resistance to weathering
• Better adhesion
• Higher stiffness modulus
• Lesser cracking, ravelling, deformation creep
  failure
• Reduce number of overlays
• Reduction in vehicle operation cost

32
Types of Modifiers
Synthetic Elastomers SBS, SBR etc.
Polymers
Plastics
Rubbers
Crumb Rubber
Natural Rubber (Latex)
Thermoset Epoxy Resins
Plain
Thermoplastic LDPE, EVA, EBA
Chemically Treated
33
Properties of Modifier

• Be compatible with Bitumen
• Blend with Bitumen properly thoroughly
• Improve temperature resistance of Bitumen
• Resist degradation of Bituminous mix
• Be capable of being processed by conventional
  mixing plants and laying machinery
• Produce coating viscosity at application temp.
• Maintain premium properties during
  storage,application and in service.
• Be cost-effective considering life cycle cost

34
MODIFIED BITUMEN

• EMULSIONS

35
MODIFIED BITUMEN EMULSIONS

• It is an Emulsion of Modified Bitumen
• Has the advantages of Modified Bitumen
  Emulsions both
• Natural Rubber Modified Bitumen Emulsions
• Polymer Modified Bitumen Emulsions

36
MULTIGRADE

• BITUMENS

37
MULTIGRADE BITUMEN

• Resists cracking at low temperature
• Resists deformation at high temperature
• Reduced rutting at heavy traffic loads
• Reduced cracking due to high traffic frequencies
• Resists Aging
• Optimize adhesion
• Optimize emulsability

38

• Thank You