Chapter 9 Flashcards
Roads
- Urban roads
- Rural roads
Characteristics of urban roads
- Traffic congested
- Short travel distance
- Less rough road surface
- Max speed: 70km/h
Characteristics of rural roads
- Less congested
- Long travel distance
- Rough road surface
- High travelling speed
Parts of a road section
- Drain
- Side table / shoulder
- Carriageway / riding surface
- Crown
Type of carriageway
- Single
- Dual
Type of road construction
- Flexible pavement
- Rigid pavement
Advantages of flexible pavement
- It has good non-skid properties
- Reasonably good appearance
- Cheap to reinstate
Disadvantages of flexible pavement
- Initial cost slightly more expensive than concrete road
- High maintenance cost
Advantages of rigid pavement
- Initial cost is considerably low
- Good resistance to skidding
- Can last for many years if well constructed
Disadvantages of rigid pavement
- Very liable to subsidence damages
- Causes glare from the sun
- Expensive to reinstate
Terms used in road construction
- Sub-base
- Road-base
- Surfacing
- Formation
Purpose of road maintenance
- Ensure that ponding does not occur
- Ensure that cross fall is retained
- Ensure that the road defects are corrected
Main defects in bituminous surface roads
- Corrugation
- Cracking
- Slick surface
Types of bituminous materials
- Tar
- Pitch
- Asphalt
Factors of bituminous materials
- Relatively inexpensive
- Durability
- Waterproofing
- Low boiling point
Bituminous mixtures materials for road
- Coarse aggregate
- Fine aggregate
- Filler
- Binder
Properties of bituminous materials
- Durability
- Workability
- Strength
- Flexibility
Bituminous mixtures usage in building
- Roof waterproofing
- Damp proof course
- Expansion joints
- Industrial flooring
Bituminous tests
- Penetration test
- Softening point test
Types of wearing course materials
- Fine cold asphalt
- Mastic asphalt
- Hot rolled asphalt
Pavement joints
- Isolation
- Contraction
- Expansion
- Shrinkage
Materials for concrete joints
- Flexible board
- Dowel bars
- Sealants (E.g. Hot poured, cold applied, pre-formed elastomeric)
Pathway construction
- Initial cost
- Skid resistance
- Wearing qualities
- Appearance required
- Maintenance cost
Types of pathways
- Pre-cast concrete paving slab
- Cast-in-situ concrete paving
- Tarmacadam, tar paving
Types of compacting equipment
- Tamping roller
- Trench compactor
- Pneumatic tyred roller
- Sheepsfoot roller
Compacting equipment used for small scale operation
- Tamping roller
- Trench compactor
Compacting equipment used for larger site
- Pneumatic tyred roller
- Sheepsfoot roller
