Shared Flashcard Set

Details

Road Design and Maintenance
Rdm
76
Civil Engineering
Undergraduate 2
11/05/2011

Additional Civil Engineering Flashcards

 


 

Cards

Term
Shadow Pricing 
Definition
Adjustment to account for inequality of market price and social goals
Term
method used to estimate the daily number of heavy vehicles
Definition

WIM data.

Term
Transit New Zealand (TNZ) specification for skid resistance
Definition

T/10

Term
typical design period for an unbound granular pavement?
Definition

25 years

Term
The main function of a tack coat
Definition

To provide a bond between a basecourse and surface dressing.

Term
What type of damage best reflects the failure of an unbound granular pavement
Definition
Rutting and increased roughness
Term
The skid resistance of a polished stone is measured by
Definition
British Pendulum Test
Term
The database used in New Zealand for storing reported accidents is known as
Definition

CAS

Term
The addition of diesel to bitumen has the effect of
Definition
Permanently reducing the hardness of bitumen
Term
First Year Rate of Returns are
Definition
Used to help determine the best start date for a project
Term
method for measuring subgrade support in the field
Definition
Cone Penetrometer
Term
The setting of “criteria for acceptable serviceability” is undertaken at the
Definition
Network Management Level
Term
SII (Surface Integrity Index) is an example of which type of composite index
Definition
Statistically derived index
Term
An Intersection Direction sign would be classified as a
Definition
Guide sign
Term
Signs with a black background and red border are classified as a
Definition
Regulatory sign
Term
A Belisha Beacon is best described as
Definition
A night only light located at Pedestrian-crossings.
Term
The TNZ Specification for pavement marking is
Definition
P/12
Term
A lighting lantern is defined as
Definition
The apparatus controlling the light distribution
Term
In the empirical method of pavement design the subgrade strength is defined by
Definition
CBR values
Term
A maintenance intervention level indicates
Definition

 A level of deterioration where it is appropriate to undertake maintenance repairs.

Term

Lime stabilisation

Definition
Lime stabilisation involves the spreading of lime oxided (CaO) which is then watered (slaked) to form lime hydroxide (Ca(OH)2) and mixed into the subgrade soil. The lime hydroxide reacts with the aluminate and silicate minerals found in almost all clayey soils
Term
Benifits of Lime Stabilisation
Definition

The advantage is that it often provides significant increases in soil strength over a relatively short time period.

Term

 Foam bitumen

Definition
The process involves coupling a bitumen tanker to the stabilizing hoe. The hot bitumen is pumped into the stabilising hoe where it is injected along with a small quantity of water through a spray bar fitted to the rotor chamber of a stabilising hoe. The water causes the hot bitumen to expand and foam inside the rotor chamber where it is mixed with the pavement material prior to re-compaction
Term

Penetration grade as a property of surface design

Definition

Bitumen is defined in New Zealand by the penetration grade, which is a measure of the hardness of bitumen and the temperature susceptibility of the bitumen.  

Term

Cationic emulsions as a property of surface design

Definition

The most commonly used in road surfacing is anionic and cationic emulsions.  The terms anionic and cationic stem from the electrical charges surrounding the bitumen globules. Positively charged bitumen particles will move to the cathode and the emulsion is known as cationic.

Term

Micro texture as a property of surface design

Definition

The micro texture is also known as a degree of polish of the exposed aggregate. The resistance of polishing of the aggregate is measured by the PSV test.

Term
List major road user benefits considered in the Land Transport New Zealand Economic Evaluation procedure
Definition
  • travel time cost savings (including those gained from reduced traffic and improved trip reliability)
  • vehicle operating cost (VOC) savings
  • accident cost savings
  • comfort and productivity benefits from sealing an unsealed road
  • driver frustration reduction benefits from passing options
  • benefits from reducing or eliminating the risks of damage.
  • carbon dioxide reduction benefits
  • other external benefits
  • national strategic factors.

 

Term

  Luminance.

Definition

Measure of the light coming off a surface in a given direction.  The unit is candelas per square metre.

Term
Prohibitory Signs
Definition
These signs indicate that a road user must not take a particular action e.g. RG-7 No Right Turn sign.
Term

 Edge Lines

Definition

Road markings used to delineate the left hand edge of a traffic lane.

Or separate a paved shoulder from the traffic lanes.

Or provide useful guidance to motorists at night and during inclement weather

Term

Asset Inventory

Definition
Inventory data on road characteristics, condition, traffic etc. Predominantly stored in the asset database eg RAMM
Term

A recent chipseal job on a winding, hilly section is showing signs of chip loss on the inside of the corners and there is also some bleeding and rolling of chips (corrugation). List reason(s) why this occurred 

Definition

Over-application of binder

            Insufficient construction rolling

            Poor post-construction traffic control

            Excessive traffic stress for the seal design used causing chip rollover

 

Term

A recent chipseal job on a winding, hilly section is showing signs of chip loss on the inside of the corners and there is also some bleeding and rolling of chips (corrugation).

Suggest methods for ensuring that it does not occur in the first place

Definition

Good seal design including: harder binder, PMB, ensuring proper rolling, adequate traffic control during early seal life, use of  racked in seal or dry locking coat.

Term
List the MAIN steps you would take in planning and executing the inspection of a short length (say 500 metres) of rural state highway
Definition

Define the asset to be assessed

Research the available data on the section concerned 

Plan the inspection (weather, time of day etc) based on the MAIN purpose of the inspection (drainage, skid resistance etc)

Organise appropriate traffic control measures

Undertake the work

Report the findings

Term
What are the major design objectives for intersections
Definition

- safety for vehicle occupants

- safety for pedestrians and cyclists

- comfort for vehicle occupants

- environmental/asthetic fit

- Effective with land use

- Effective aid to traffic flow

Term
List effective parameters that are used to increase the effectiveness of intersections
Definition

- Adequate sight distance

- Adequate stopping distance

- Merge in/out acceleration and decceleration distance

- signage

- lighting

- control measures

- geometry

Term
Standard axle load of a SAST
Definition
53kN
Term
Standard axle load of a SADT
Definition
80kN
Term
Standard axle load of a DADT
Definition
135kN
Term
Standard axle load of a TADT
Definition
181kN
Term
ANIONIC EMULSION
Definition

a bituminous emulsion

which has a negative charge conferred on each

bitumen droplet.

Term
APPLICATION RATE
Definition

For BINDER, the amount of

material applied to a given area of road surface,

expressed in litres per square metre (L/m2). For

CHIP, application rates are traditionally specified

in terms of area per volume (m2/m3).

Term
AVERAGE GREATEST DIMENSION (AGD):
Definition

the

average of the greatest dimension of a sample of

chips, aligned in their greatest dimension.

Term
AVERAGE LEAST DIMENSION (ALD):
Definition

the average

of the least dimension of a sample of chips. The

least dimension of a chip is the distance between

two parallel plates in contact with the chip when

the chip is placed so that the distance is a minimum.

Term
BITUMEN EMULSION:
Definition

a liquid in which a

substantial amount of bitumen or bituminous

binder is dispersed as fine droplets (the DISPERSED

PHASE) in water (the CONTINUOUS PHASE), and

stabilised by means of one or more emulsifying

agents. It is available in two basic types, CATIONIC

and ANIONIC, and in several grades (Quick Break,

Slow Break, or Stable Grades), according to the rapidity

of BREAKING (setting).

Term
BENKELMAN BEAM
Definition

an instrument for measuring

the deflection of the surface of a pavement caused

by the passage of a dual-tyred single axle carrying

a standard axle load.

Term
BPT (BRITISH PENDULUM TESTER):
Definition

device for

measuring the surface friction or SKID RESISTANCE

of a pavement surface.

Term
CATIONIC EMULSION
Definition

a bitumen emulsion which

has a positive charge conferred on each bitumen

droplet.

Term
CALCINED BAUXITE
Definition

a very high PSV (high skid

resistance) chip produced by heating bauxite ore

in a kiln. Applied as a high skid resistance road

surfacing using epoxy or polyurethane as a binder.

Term
CALIFORNIA BEARING RATIO, CBR:
Definition

a ratio

expressed as a percentage between a test load and

a standard load. A standardised testing procedure

(initiated by Californian State Highways

Department in 1929) for comparing the strengths

of basecourses for roads (and airfields).

Term
CEMENT STABILISATION
Definition

the controlled

application of CEMENT to improve the loadcarrying

capacity of a pavement layer (usually the

BASECOURSE) or the SUBGRADE

Term
DENSE-GRADED MIX
Definition

a bituminous mix made

with graded chip, with or without added mineral

filler and low in voids. It depends on grading for

stability

Term
CUTBACK BITUMEN
Definition

a

bitumen the viscosity of which has been temporarily

reduced by the addition of a volatile diluent

(CUTTER), such as KEROSENE, to make it more

fluid for ease of application.

Term
DRY LOCK SEAL
Definition

an application of small chip to

a new chipseal, usually after some traffic has used

the new seal. No binder is applied before spreading

the dry lock chip.

Term
FALLING WEIGHT DEFLECTOMETER (FWD)
Definition

device to measure surface deflection of a pavement

under a dynamic load in order to evaluate its

structural adequacy.

Term
FOAMED BITUMEN
Definition

is a hot

bituminous binder which is temporarily converted

to a foamed state by the addition of about 2% (by

weight of bitumen) of water in controlled

conditions.

Term
GAP GRADED
Definition

an aggregate or chip with both fine

and coarse material but without one or more of

the intermediate size fractions

Term
HOT MIX ASPHALT (HMA)
Definition

aggregate and

bitumen heated and mixed while hot, transported

to the site of construction, laid and compacted

while hot

Term
LIME STABILISATION:
Definition

the controlled application

of lime to improve the load-carrying capacity of a

pavement layer (usually the basecourse), or of the

subgrade.

Term
MECHANISTIC ANALYSIS
Definition

a design procedure

based on stress analysis and on elastic material

behaviour in pavements.

Term
NUCLEAR DENSOMETER
Definition

an instrument for the

non-destructive measurement of the density and

moisture content of pavement layers.

Term
OGEM, OPEN GRADED EMULSION MIX / OGPA, OPEN GRADED POROUS ASPHALT
Definition

a gapgraded

hot mixed asphalt containing a mix of

binder and larger sized aggregates with only small

amounts of fine material, with relatively high void

content, and depending largely on mechanical

interlock for stability. It has interconnected voids

which aid drainage of road surface water.

Term
PENETRATION GRADE
Definition

determines the hardness

of a roading bitumen by measuring the distance

in tenths of a millimetre that a standard needle

weighted with 100 g will sink (penetrate) in

5 seconds into a bitumen sample, at 25°C.

Term
PMB (POLYMER MODIFIED BITUMEN):
Definition

a

bitumen with polymer added, usually up to 5-6%

by mass. Polymers tend to reduce the temperature

sensitivity of the binder, and some polymers make

the binder more elastic.

Term
POLISHED STONE VALUE (PSV):
Definition

a measure of

how a stone will polish under standard conditions.

The PSV test is primarily used to identify aggregates

(chip) that will retain their microtexture (i.e. will

not polish) under traffic.

Term
QUICK LIME:
Definition

calcium oxide, CaO, used as an

additive (with granular form) in soil stabilisation.

Also referred to as Burnt Lime.

Term
RACKED-IN CHIPSEAL
Definition

one application of binder

and two applications of chip are made in the

following sequence:

• A single application of binder is applied, followed

by application of a large chip;

• A further application of a smaller chip is made.

The first application of large chip has spaces into

which the smaller chip can fall between the large

chip, and adhere to the layer of binder below.

Term

RAMM (Road Assessment and Maintenance

Management system):

Definition

a computer-based system

to manage the maintenance and rehabilitation of

pavements and associated roading features.

Term
RESIDUAL BINDER
Definition

the non-volatile fraction of

a binder that remains in service after evaporation

of volatiles.

Term
RCA or ROAD CONTROLLING AUTHORITY
Definition

the

authorities responsible for roading within their

jurisdiction, e.g. Transit New Zealand for the

national State Highway system; District or City

Councils for roads within Local Government regions

including roads within urban boundaries.

Term
SAND CIRCLE:
Definition

a test used to determine the average

texture depth of a pavement surface. A circle is

made with a standard volume of sand, and its

diameter relates to the volume of voids. The test

is in accordance with TNZ T/3 Specification:

Measurement of texture by the Sand Circle Method.

Term
SINGLE COAT CHIPSEAL
Definition

a single sprayed

application of sealing binder followed immediately

with a single application of chip which is spread

and rolled into place.

Term
STONE MASTIC ASPHALT (SMA)
Definition

gap-graded

hot mixed asphalt which has a high proportion of

coarse aggregate that interlocks to form a stoneon-

stone skeleton to resist permanent deformation.

The stone skeleton is filled with a mastic of bitumen

and filler to which fibres are added to provide

adequate stability of the bitumen, and to prevent

drainage of binder during transport to the site and

placement.

Term
TRIAXIAL TEST
Definition

a test to determine the stress–strain

properties of a pavement material in which a

cylindrical specimen of the material is subjected

to a 3-dimensional stress system. The axial strain

is related to the applied stress.

Term
TWO COAT CHIPSEAL
Definition

a chipseal with two

applications of binder and two applications of chip

applied in the following sequence:

• an application of sprayed binder followed

immediately with an application of large size

chip;

• a second application of sprayed binder, and

another application of finer chip.

Both coats are applied one after the other with

little to no time delay between coats.

Term
WET LOCK SEAL
Definition

a seal coat applied to another

seal with a light application of binder.

Supporting users have an ad free experience!