Vocabulary Flashcards
Pavement
Portion of a road designed for vehicular traffic.
Alignment
The geometric form of the centerline (or other reference line) of a carriageway in both the horizontal and vertical directions.
Batter
The uniform side slope of walls, banks, cuttings, etc. usually expressed as a ratio of horizontal to vertical. Eg. 1:1 or 2:2 (45 degree angle).
Berm
- An area between the kerb (curb) and footpath, or between the footpath and property boundary.
- Verge.
Datum
A defined horizontal or level plane to which the relative elevation of other points may be referred.
Chainage
The distance of a point along a control lane measured from a datum point.
Crossfall
The slope measured at right angles of the alignment of the surface of any part of a carriageway.
Cross-section
A vertical section generally at a 90 degree angle to the centerline showing the ground. On drawings, it commonly shows the road to be constructed or as constructed.
Crown
The highest point on the cross-section of the carriageway with a two-way crossfall.
Cul-de-sac
A street or road for vehicular traffic at one end only.
Road
Link in the network that exits to carry traffic reasonably and efficiently on which severe traffic restraints is inappropriate (includes “arterials”, “main roads”, and other traffic routes.
AADT
Annual Average Daily Traffic
AHD
Australian Height Datum (determined by average sea level)
RRPM
Raised Reflective Pavement Markings (raised safety devices on roads)
VPD
Vehicles per day
ESA
Equivalent Standard Axle
A standard axle load which has been defined to allow traffic count data to be converted into load on road pavement
LATM
Local Area Traffic Management
CBR
California Bearing Ratio
penetration test for evaluation of the mechanical strength of road subgrades and basecourses
HMA
Hot Mix Asphalt (asphalt concrete pavement).
AS
Australian Standards
MRWA
Main Roads Western Australia
3 main authorities related to roads?
- Main Roads WA
- AS
- Austroads (NZ & Aus)
A rigid pavement produces a…
relatively uniform distribution of stress on the subgrade.
Under a wheel load, a flexible pavement…
deforms and produces a relatively concentrated stress distribution on the subgrade.
How many classes of vehicles are there?
12 according to austroads.
3 main categories are: a) light vehicles, b) heavy vehicles and c) long vehicles and road trains.
Types of kerbs
barrier
semi-barrier
mountable
semi-mountable
Difference between crossover and driveway?
Driveway is inside private property, crossover is outside it.
Stabilization (of a road)
Improvement of the soil material by mechanical or chemical means.
The 2 types of vertical curves are
1) Sag
2) Crest
5 types of horizontal curves are
1) Simple curve
2) Compound curve
3) Broken-back curve
4) Reverse curve
5) Transition curve
Flexible pavement is surfaced with
bituminous (or asphalt) materials.
Rigid pavements are composed of a surface of
PCC (Portland cement concrete).
The main layers of a rigid pavement are
BASE (reinforced or un-reinforced concrete)
SUBBASE (gravel)
SUBGRADE (in-situ natural material)
The main layers of a flexible pavement are
SURFACE (bitumen/asphalt)
BASE (HMA and aggregates)
SUBBASE (gravel)
SUBGRADE (in-situ natural material)
Austroads classifies RURAL roads into 5 classes
Class 1 to 5.
1, 2, 3 arterial,
4, 5 local.
Austroads classifies URBAN roads into 4 classes
Class 6 (busiest) to 9.
6, 7 arterial
8, 9 local.
Which Austroads class is a mini bus or a bicycle?
Class 1
Which Austroads class is a car towing a caravan?
Class 2
Which Austroads class is a standard bus or a 2-axle truck?
Class 3
3 methods used in MANUAL traffic counts
1) tally sheets
2) mechanical counting boards
3) electrical counting boards
Traffic volume studies are conducted to determine the
number, movements and classifications of roadway vehicles at a given location.
3 methods used in AUTOMATIC traffic counts
1) Portable counters
2) Permanent counters
3) Videotape
ADT
Average Daily Traffic (24hr count at a specific location).
3 elements which define how a road will perform
- vehicle input
- human input
- load
4 P’s regarding
Dial Before you Dig
1) Plan
2) Pothole
3) Protect
4) Proceed
How long do responses generally take to give you service locations from Dial Before you Dig?
From 2 min to 2 days
Location Services:
- Telstra cables (telecom)
- Sewer pipes (water corp)
- NBN (telecom - fibre optic)
- Gas pipes
- Potable water
- Electricity/power (Western Aus.)
In regards to automatic count method, what data can be identified when the counts are recorded daily (ie full 24hrs)?
The peak flow period data.
In a dwg, which symbol identifies
a) an existing sign?
b) to-be-installed sign?
a) o|
b) •|
DIR for 1 and 2 directions
For 1: 1
For 2: 0.5
Definition of Rural Road (class 1)
Those roads which form the principal avenue for communications between major regions of Australia including direct connections between capitals and cities.
Definition of Urban Road (class 6)
Those roads whose main function is to perform the principal avenue of communications for massive traffic movement (arterial road).
Sign types
R= regulatory signs W= warning signs G= guide signs T= temporary signs D= hazard markers
Types of soils
Gravel Sand Clay Silt Peat (vegetable matter soil)
Maintenance treatments on pavements
Pothole restoration
Edges repairs
Crack resealing
Rehabilitation treatments on pavements:
Partial reconstruction
Overlay
Surface resealing
Two causes of scouring of unsealed roads:
- Concentration of water flows
- Erodible base
Types of surface deformation:
- crocodile
- block
- transverse
Types of pavement (below surface) deformation:
- shoving
- rutting
- depression
