highway engineering

1. HIGHWAY MATERIALS
Part 4
Bitumen
Mr Che Ros Ismail| Dr Norhidayah Abdul Hassan
Faculty of Civil Engineering

2. 2
Road
materials
Aggregate
Binder
Filler

3. Content
Origin and Production
Composition and Types of Bitumen
Bitumen Properties
Grading Systems
Tests on Bitumen Properties

4. 4
Origin
Bitumen
Source
Natural
Petroleum
- in geological strata,
(Trinidad lake and
rock pores)
- by products of distillation
of crude oil

5. Bitumen Composition
Molecular
80-85%
Carbon
10%
Hydrogen
1-5%
Sulphur
1%
Nitrogen
<1%
Oxygen

6. Bitumen Composition
Asphaltenes
Maltenes
(Resins,
Aromatics
and
Saturates)
Bitumen
Component

7. 7
Types of
bitumen
Emulsion
Conventional
bitumen
Cutback
Foamed
bitumen

8. Conventional
bitumen
 Strong and
durable
 Black, sticky,
semisolid and highly
viscous
 Largest use in HMA
 Strong as paving
material

9. 9
Bitumen
Properties
Rheology
Durability
Safety
Purity

10. Grading System
10
 Penetration Grade: based on penetration test,
(1PEN=0.1mm), high PEN (100-150) for cold climate, low
PEN (30-40) for hot climate
 Viscosity Grade: based on viscosity test, unit in poises,
Ex. AC-20, AR-4000
 Performance Grade: based on extreme hot and cold
pavement temperature, ave. 7 days maximum & minimum
temp. in ◦C, Ex. PG 64-16, rheological properties

11. Cutback Bitumen
 Liquid bitumen = petroleum solvent + bitumen(50-
80%)
 Low viscosity for lower application temperatures
 Three types:
11
Rapid Curing – bitumen + gasoline (RC-70)
Medium Curing - bitumen + kerosene
Slow Curing – bitumen + diesel

12. Emulsified Bitumen
12
 Liquid bitumen = Bitumen (40-75%) + water (25-60%) +
emulsifier (0.1-2.5%)
 Low viscosity for lower application temperatures
 Two most commonly used emulsions:
i. Anionic (-ve) – used with aggregate such as limestone
ii. Cationic (+ve) – used with aggregates such as
sandstone
 Graded according to setting rate:
Rapid Set
Medium Set
Slow Set, SS1K

13. Bitumen Tests
13
Penetration
Softening Point
Ductility
Viscosity
Solubility

14. Bitumen Tests
14
Flash and Fire Point
Loss on Heating
Rolling Thin Film
Oven test/Pressure
Aging Vessel
Dynamic Shear
Rheometer

15. Thank You