Abu Dhabi, United Arab Emirates. STANDARD CONSTRUCTION SPECIFICATIONS (PART 1 - ROADS, Second Edition 2020)

labor shall be used so that there is continual production and distribution of the asphalt course being
constructed. Intermittent or “STOP & GO” type of operations will not be permitted by the Engineer.

Equipment approved for use shall not be removed from the site without the approval of the Engineer.

Contractor shall furnish the Engineer with the manufacturer's catalogues, specifications and other
published data for the equipment and machinery he proposes to use.

a. Mixing Plant

All plants used by the Contractor for the preparation of asphalt hot mixes shall comply with all the
requirements of Paragraph 1 of Sub-article (a) of Article 3.3.3.1. In addition, batch mixing plants
shall comply with the requirements of Paragraph 2 of Sub-article (a) of Article 3.3.3.1.

1. Requirements for all Plants

Automatic Operation

Plant shall be designed, coordinated and operated so as to continually produce asphalt mix
within  the  job  mix  tolerances  specified.  Plant  shall  be  equipped  and  operated  so  that  the
proportioning of the hot aggregate, commercial filler and bitumen, together with the dry and
wet mixing cycles, are all controlled automatically.  Positive interlock shall be provided so that
proportioning,  mixing  and  discharge  are  accomplished  by  one  operation  without  manual
control of the separate phases.

Cold Feed System

Plant shall include a sufficient number of cold storage bins so that there is at least one bin for
each  different  stockpile  of  material  being  used.    Intermixing  of  material  from  different
stockpiles in one bin or on the ground prior to putting into the bin is prohibited.  Cold bins and
loading equipment used shall be compatible to prevent overflow between bins. Baffle plates
shall also be used between bins to prevent overflow of one bin into another. Each cold bin
shall  include  an  accurate  means  for  continuously  feeding  the  required  amount  of  mineral
aggregate so that uniform production shall be approved by the Engineer and shall be checked
and calibrated as often as he may deem necessary to ensure its continued accuracy. Change
of settings shall be made only with the approval of the Engineer.

Drier

A drier of satisfactory design shall be provided. Drier shall be capable of uniformly drying
and heating the aggregate to the moisture and temperature required without leaving any
visible unburned oil or carbon residue on the aggregate when discharged from the drier.

Dust Collector

Plant shall be provided with a dust collector designed to waste, or to return in a constant and
uniform flow to the hot elevator, all or part of the material collected. Prior to permitting the
return of such collected dust, the Engineer will examine its characteristics in relation to the
mix requirements and will designate the quantity to be returned.

Plant shall have a screen cover and such additional housings and emission control equipment
as may be necessary to ensure the proper control of dust in accordance with all local
regulations relating to control of dust.

Screens

Plant  screens  shall  be  capable  of  screening  all  aggregates  to  the  specified  sizes  and
proportions.  They shall have capacities equal to or greater than the maximum rated capacity
of the plant.  Screens shall be placed directly above the storage bins for the heated aggregate
and shall receive the material coming from the drier.  They shall have an operating efficiency
such that the aggregate deposited in any bin shall not contain more than 10 % of oversize or
undersize  material.    This  screen  tolerance  shall  not  invalidate  the  job  mix  tolerances
specified.

Hot Bins

Plant shall include at least three storage bins for hot aggregate of sufficient size to supply the
pugmill when it is operating at full capacity.  They shall be arranged to ensure separate and
adequate  storage  of  appropriate  fractions  of  the  aggregate.    Each  compartment  shall  be
provided with an overflow pipe that shall be of such size and at such location as to prevent
any backing up of material into other bins or against the screens.  Bins shall be so constructed
that  samples  can  be  readily  obtained  therefrom.    An  additional  dry  storage  bin  shall  be
provided for commercial mineral filler and provision shall be made for proportioning this filler
into the mix.

Equipment for Preparation of Bituminous Material

Tanks for storage of bituminous material shall be equipped for  heating the material, using
positive  and  automatic  control  at  all  times,  to  a  temperature  within  the  specified  range.
Heating shall be accomplished by steam coils, hot oil, electricity or other approved means
such  that  no flame shall  come  in  contact  with the  heating  tank.  Circulating  system for  the
bituminous  material  shall  be  of  adequate  size  to  ensure  proper  and  continuous  circulation
during the entire operating period. Suitable means shall be provided either by steam or hot
oil  jackets  or  other  insulation  for  maintaining  the  specified  temperature  of  the  bituminous
material in the pipeline, meters, weigh buckets, spray bars, and other containers and flow
lines.  Storage tank capacity shall be sufficient for at least one day's operation.  Circulation
return  lines  to  the  asphalt  storage  tanks  shall  be  submerged  to  the  same  elevation  in  the
storage tanks as the feeder line (two or three vertical slots may be cut in the return line above
the high level mark to break vacuum when reversing the pump).

Contractor shall provide a sampling outlet in the bituminous material feedline connecting the
plant storage tanks to the bituminous material weighing or metering box. Outlet shall consist
of a valve installed in such a manner that samples may be withdrawn from the line slowly at
any time during plant operation. Location of the sampling outlet shall be readily accessible
and free from obstruction. A drainage receptacle shall be provided for flushing the outlet prior
to sampling.

Thermometric Equipment

An armored thermometer reading from 38



C to 204



C shall be fixed in the bituminous feed

line at a suitable location near the discharge valve at the pugmill. Similar devices shall be
fixed in the heating and storage tanks.

Plant shall be further equipped with either an approved dial-scale, mercury-actuated
thermometer, an electric pyrometer, or other approved thermometric instruments placed at
the discharge chute of the drier and in the hot fines bin so as to register automatically or
indicate the temperature of the heated aggregates. For better regulation of the temperature
of the aggregates, replacement of any thermometer by an approved temperature-recording
apparatus may be required by the Engineer and he may further require that daily temperature
charts be submitted to him by the Contractor.

Control of Mixing Time

Plant shall be equipped with positive means to govern the time of mixing and to maintain it
constant unless changed at the direction of the Engineer.

Pugmill

Pugmill shall include equipment to deliver the bituminous materials in a thin uniform sheet or
in multiple sprays over the full length of the mixer.

Temporary Storage of Mix

Plants may be equipped with skiffs or elevators for delivering hot mix to hoppers or silos
before discharging to hauling units. Skiffs or elevators shall not be sprayed with diesel or
other solvents; where necessary they may be sprayed with a minimum amount of lime water,

soap or detergent solution. Hoppers or silos shall be of such design that no segregation or
loss in temperature of the mix occurs.

Safety Requirements

Adequate and safe stairways to the mixer platform and guarded ladders to other plant units
shall be placed at all points required for accessibility to all plant operations. Accessibility to
the top of truck bodies shall be provided by means of a platform or other suitable device to
enable  the  Engineer  to  obtain  mixture  temperature  data.    To  facilitate  handling  scale
calibration equipment, sampling equipment, etc., a hoist or pulley system shall be provided
to raise or lower the equipment from the ground to platform or vice versa.  All gears, pulleys,
chains,  sprockets  and  other  dangerous  moving  parts  shall  be  thoroughly  guarded  and
protected.  Ample and unobstructed passage shall be maintained at all times in and around
the  truck  loading  space.    This  space  shall  be  kept  free  from  drippings  from  the  mixing
platform.

Environmental Control

Prior to the Engineer's approval of the asphalt plant, current certifications must be submitted
that establishes the Department has inspected and approved the environmental control
devices fitted to the plant and that it is in full compliance with the Government's current
regulations related to protection of the environment.

2. Special requirements for Batching Plant

Weigh Box Hopper

Plant shall include means for accurately weighing each size of aggregate in a weigh box or
hopper, suspended on scales, ample in size to hold a full batch without hand raking or running
over.  Weigh box or hopper shall be supported on fulcrums and knife edges so constructed
that they will not be easily thrown out of alignment or adjustment.  All edges, ends and sides
of weighing hoppers shall be free from contact with any supporting rods and columns or other
equipment that shall in any way affect the proper functioning of the hopper.  There shall also
be sufficient clearance between hoppers and supporting devices to prevent accumulations of
foreign materials.  Discharge gate of the weigh box shall be so hung that the aggregate shall
not be segregated when dumped into the mixer and shall close tightly when the hopper is
empty so that no material is allowed to leak into the batch in the mixer during the process of
weighing the next batch.

Scales and Meters

Scales or meters used for  proportioning aggregate, commercial filler  and bitumen shall be
accurate to one percent of the indicated quantity.  Scales and meters shall be substantially
constructed  and  those  that  are  sensitive  and  that  easily  get  out  of  adjustment  shall  be
replaced.    Scales  shall  be  constructed  and  located  so  as  to  prevent  vibration  in  the  dial
pointer.

Scales for weighing aggregate and commercial filler may be either the beam or springless
dial type and shall be of standard make and design. Graduation intervals shall be not more
than  0.1  %  of  the  nominal  scale  capacity.    Dial  scales  shall  be  equipped  with  adjustable
pointers for controlling automatically the weighing of each aggregate and filler.  Pointer shall
be set close to the dial face to prevent excessive parallax and all dial faces shall be so located
that  they  shall  be  in  plain  view  of  the  operator  at  all  times.    Weighing  sequence  of  hot
aggregates shall progress from coarse to fine.

Bituminous material shall be automatically proportioned by either weighing or metering.  The
minimum  graduation  shall  be  not  more  than  1  liter  or  1  kg.  Bituminous  scales  and  weigh
buckets shall be such that the required amount of bitumen is provided in a single weighing
and delivered to the pugmill without loss due to overflow, splashing or spillage.  Bituminous
weigh  buckets  shall  be  satisfactorily  insulated  to  prevent  loss  of  heat  in  the  bitumen  or
accumulation of bitumen in the bucket.  Bituminous metering devices shall be rotating positive

displacement pumps and shall be capable of providing the designated quantity of material for
each batch.

All scales and meters shall be approved by the Engineer and shall be checked and calibrated
as often as he may deem necessary to ensure their continued accuracy. Contractor shall
provide and have at hand the necessary standard weights and other necessary equipment
in order to perform testing and calibration of all scales and meters in a practical manner. An
accurate platform scale with a capacity of 250 kg or more and an accuracy of 0.5 % of the
load shall also be provided.

Pugmill Mixer

Batch mixer shall be an approved twin pugmill type, capable of producing a uniform mixture
within the job-mix tolerances.  Batch mixer shall be of such design to permit visual inspection
of the mix.  Mixer shall be so constructed as to prevent leakage of contents and its capacity
shall not be less than 600 kg per batch.  Mixer shall be enclosed and shall have an accurate
time lock to control the operation of a complete mixing cycle by locking the weigh box gate
after  the charging  of  the  mixer  until  the  closing of  the mixer  gate  at the completion  of  the
cycle.  Mixer shall lock the bitumen supply throughout the dry mixing period and shall lock
the mixer gate throughout the dry and wet mixing periods.  Dry mixing period is defined as
the  interval  of  time  between  opening  of  the  weigh  box  gate  and  the  start  of  application  of
bitumen.

Wet mixing period is the interval between the time the bituminous material is spread on the
aggregate and the time the mixer gate is opened. Control of the time shall be flexible and
capable of being set at intervals of not more than five seconds throughout cycles up to three
minutes. A mechanical batch counter shall be so designed as to register only completely
mixed batches.

Mixer shall be equipped with a sufficient number of paddles or blades in a suitable
arrangement to produce a proper and uniformly mixed batch. The clearance of blades from
all fixed and moving parts shall not exceed 20 mm except in the case of aggregates having
a nominal maximum size of over 25.4 mm in which case the clearance shall be so adjusted
as to prevent undue breakage of the coarse aggregate during the mixing operation.

Asphalt Plant shall meet the requirements of ASTM D 995. The plant shall be equipped with
facilities to provide computer printout. The print out shall indicate the quantity of the materials
in each batch against their respective target value. The print out shall contain the following
information:

Batch time , temperature of aggregates , temperature of bitumen , temperature of mix,
quantity of aggregates from different hot bin , the quantity of filler and quantity of bitumen (
by weight of total mix ).

A copy of full set of computer printout covering full

day’s protection shall be handed over to

the Engineer at the end of the day’s production

Hauling Equipment

Vehicles used for the transport of aggregates or bituminous mix shall have tight, clean and smooth
metal beds and shall be free from dust, screenings,  petroleum oil, volatile or other mineral spirits
which may affect the material being hauled.  Vehicle metal bed shall, if required, be sprayed with a
minimum amount of soapy water or lime solution to prevent bituminous mix from adhering to the bed.
After  spraying,  the  truck  shall  be  raised  and  thoroughly  drained;  no  excess  solution  shall  be
permitted. Use of diesel or other solvents to spray in the truck bed is prohibited. Provision shall be
made for covering truck loads with canvas or other suitable material of such size as to protect the
bituminous mix from the weather.

When  necessary,  in  order  that  a  bituminous  mixture  be  delivered  on  the  road  at  the  specified
temperature, truck beds shall be insulated to obtain workable temperature of the mix and all covers
shall  be  securely  fastened.    Any  truck  causing  excessive  segregation  of  material  by  its  spring
suspension  or  other  contributing  factors,  or  that  shows  oil  leaks  in  detrimental  amounts,  or  that

causes undue delays, shall, upon the direction of the Engineer, be removed from the work until such
faults are corrected. End dump trucks shall be equipped with chains on the tail gates for control when
dumping the mix into the paving machine.

Contractor shall provide an adequate number of trucks of such size, speed and condition to ensure
orderly and continuous operations of the work.

b. Pavers

Use  pavers  that  are  self-contained,  power-propelled  units,  provided  with  an  activated  screed  or
strike-off  assembly,  heated  if  necessary,  and  capable  of  spreading  and  finishing  courses  of
bituminous  mixture  in  lane  and  shoulder  widths  applicable  to  the  specified  typical  section  and
thicknesses shown on the plans.

Pavers shall be equipped with a receiving hopper having sufficient capacity for a uniform spreading
operation. It shall be equipped with the screed with automatic controls which will make adjustments
in both transverse and longitudinal direction. External longitudinal reference devices used to pick up
grade information for the automatic sensing control shall conform to the following:

1. When picking up grade information from an underlying base, the external longitudinal

reference device shall be a floating beam at least 9 m long or an 8 m non-contact averaging
ski with a minimum of 4 sensors

2. When picking up grade information from an adjacent compacted pavement course or a

concrete surface, the external longitudinal reference device shall be a floating beam or a non-
contact averaging ski with a minimum of 2 sensors. Either referencing device shall be at least
3 m in length.

3. When using a floating beam to pick up grade information, place the sensing device in the

middle third of the floating beam. A non-contact sensor may be used to pick up grade
information from a newly placed adjacent compacted course only when approved.

Should the automatic controls fail to function properly, finishing the half shift with manual controls
may be approved. Do not resume until the controls are repaired.

Pavers shall employ mechanical devices as equalizing runners, straight edge runners, even arms or
other compensating devices to maintain trueness of grade and to confine the edges of the pavement
to true lines without the use of stationary side forms. Equipment shall include blending or joint
leveling devices for smoothing and adjusting longitudinal joints between lanes. Assembly shall be
designed and operated in such manner that it shall place the material at the required compacted
thickness.

Electronic screeds shall include automatic feed controls to maintain a constant level of material along
the  full  length  of  the  screed,  automatic  profile  grade  control  and  automatic  slope  control.    Profile
grade controller shall be activated by a travelling, articulated averaging beam of not less than 9.14
m in length or taut stringline (wire) set to grade.  Automatic slope control shall be equipped with a
proportioning  manual  override  to  enable  smooth  transition  of  changing  slope  rates.    Automatic
screed controls shall be approved by the Engineer prior to use.

If, during construction, it is found that the spreading and finishing equipment in operation leaves in
the pavement surface tracks or indented areas or other objectionable irregularities that are not
satisfactorily corrected by scheduled operations, the use of such equipment shall be discontinued
and other satisfactory spreading and finishing equipment shall be provided by the Contractor.

c. Rollers

Rolling equipment shall consist of vibratory steel-wheeled rollers, steel wheel rollers and pneumatic-
tired rollers as required by the Engineer for proper compaction and finishing of the asphalt surface.
Unless otherwise permitted, rollers shall be equipped with reversible or dual controls to allow
operation both forward and backward with the operator always facing in the direction of movement.

Breakdown rollers shall be a 2 axle tandem steel wheeled weighing not less than 9.1 metric tons and
capable of rolling with or without vibration.

Steel  wheel  rollers  shall  be  self-propelled  and  equipped  with  power  units  of  not  less  than  four
cylinders  and  under  working  conditions  shall  develop  contact  pressures  under  the  compression
wheels of 44-64 kN per meter of width.

Rollers shall be equipped with adjustable scrapers to keep the wheel surface clean and with efficient
means of keeping them wet to prevent mixes from sticking.  These surfaces shall have no flat areas
or projections which shall mar the surface of the asphalt courses.  Vibratory steel-wheeled rollers
shall have dual drums with a minimum weight of 62 kN.  Vibrating frequency shall be between 2000
to 3000 cycles per minute with individual controls for each tandem.

All steel-wheeled rollers shall be in good condition and the contractor shall furnish to the Engineer
the manufacturer's technical data for each roller and no roller shall be used except after approval of
the Engineer.

Pneumatic tired rollers shall weigh not less than 12 tons and be equipped with pneumatic tires of
equal size and diameter mounted on 2 axles attached to a rigid frame equipped with a loading
platform or body suitable for ballast loading. Minimum width between the outer edge of the outside
tires on a given axle is 1.5 m. Use tires with satisfactory treads. Space the tires on the rear axle so
that the entire gap between adjacent tires on the front axle will be covered by the tread of the rear
tires. Uniformly inflate the tires so that the air pressure in the tires will not vary more than 35 kPa.
Use the tire manufacturer’s recommended inflation pressure. Use a minimum tire size of 185 mm x
375 mm, 4 ply. Fully skirt roller with rigid material to within 25 mm of the pavement surface.

Pneumatic-tired rollers shall be in good condition and with enough ballast space to provide uniform
wheel loadings as may be required

Contractor shall furnish to the Engineer charts or tabulations showing the contact areas and contact
pressures for the full range of tire inflation pressures and for the full range of tire loadings for each
type and size compactor tire furnished and used in pneumatic-tired rollers.

Total operating weight and tire pressure may be varied by order of the Engineer to obtain contact
pressures which shall result in the required asphalt course density.

Finish roller shall be 2-axle tandem steel wheeled weighing not less than 7.2 metric tons.

d. Asphalt Distributor

Asphalt distributor truck shall be of the pressure type with insulated tanks. Use of gravity distributors
will not be permitted by the Engineer. Distributor shall have pneumatic tires of such width and
number that the load produced on the road surface shall not exceed 98 kN per meter of tire width.

Spray bars shall have a minimum length of 2.04 meters and shall be of the full circulating type.  Spray
bar extensions shall also be of the full circulating type.  Spray bar shall be adjustable to maintain a
constant height above the surface to be treated.  Spray bar nozzles shall be slotted and shall be of
such  design  so  as  to  provide  a  uniform  unbroken  spread  of  bituminous  material  on  the  surface.
Valves shall be operated by levers so that one or all valves may be quickly opened or closed in one
operation.  Distributor shall be equipped with a hose and nozzle attachment to be used for spotting
areas inaccessible to the distributor.  Distributor and booster tanks shall be so maintained at all times
as to prevent dripping of bituminous material from any part of the equipment.

Distributor shall be equipped with devices and charts to provide for accurate and rapid determination
and control of the amount of bituminous material being applied and with a tachometer of the auxiliary
wheel  type  reading  speed  in  meters  per  minute.    Spreading  equipment  shall  be  provided  with  a
separate  power  unit  for  the  pump  or  a  variable  displacement  pump  driven  by  a  hydrostatic
transmission  so  that  a  uniform  application  of  bituminous  material,  in  controlled  amounts,  may  be
made  ranging  from  0.15  to  5.0  kg/m

and with a range of pressure from 441 to 1,324 kN/m

Distributor shall have satisfactory heating equipment and thermometers in order to provide the full
range of application temperatures for the bituminous material being used.

Prior to the commencement of the work and as required by the Engineer, the bituminous distributor
shall be checked and calibrated such that the rate of transverse spread or longitudinal spread shall
not vary more than ten percent from the required rate of application.

e. Cold Planer

Cold planer proposed for use shall meet the following minimum requirements:

1. Specialized equipment designed specifically for the purpose of removing, and/or surface

treating or leveling asphaltic or concrete pavement using a rotating cutter mandrel.

2. Capable of cutting flush to kerbs or other vertical objects.

3. Control system capable of maintaining profiles and cross-slopes such that after planing the

resulting surface will be within plus or minus four millimeters of the required profile and cross-
slope.

4. Capable of performing single pass cuts of up to 150 mm depth.

5. Approved by the Engineer for the specific use intended.

f. Unacceptable Equipment

Engineer will have the right to stop the use of any equipment or plant which he deems to be inferior
to the quality required and to instruct the removal of such equipment and to have it replaced by
suitable equipment or to alter the method of operation at any time.

Contractor shall immediately comply with such instructions without being entitled to any indemnities
or extensions as a result of such instructions. Contractor shall not be allowed to use any equipment
or plant before obtaining the approval of the Engineer, and the Contractor shall undertake to follow
sound technical methods of operation and to engage skilled and trained operators, mechanics and
labor to carry out the works. Engineer will have the right to expel any operators, mechanics or labor
and to instruct suitable replacement thereof at any time he deems such action is necessary.

3.3.3.2 Field Trial

On the first day of bituminous mix production, produce trial mixture of 450 metric tons at the
optimum binder content. Complete production of the trial mixture the same shift. Produce the
trial  mixture  at  the  medium  speed  used  during  the  plant  calibration.  Trial  mixture  may  be
placed on the shoulder of the roadway or the passing lane of four lane roadways and become
a section of the completed roadway.  For other roadways, place trial mixture at an approved
location. Field trial mixture shall conform to job-mix formula.

Acceptance of the plant produced trial mixture will be based on test results meeting the
requirements of this section with the aggregate gradation within the job mix ranges given
and the in-place densities meeting the requirements of Article 3.3.3.8.

When test results of the trial mixture do not meet the requirements, additional plant trial
mixture may be required and the required tests performed.

A revised job-mix formula (if applicable) will be required based on the results of the tests
performed on the field trial plant produced mixtures. Asphalt content will be selected, based
on meeting the specifications for Marshall stability and percent air voids.

Should there be a change in sources of material, establish a new approved mix design and a
new job-mix formula

3.3.3.3 Weather Limitations

Production and spreading of asphaltic concrete mix shall not be permitted when the ambient
temperature is less than 8



C, nor during rain, fog, dust-storms or other unsuitable weather.

3.3.3.4 Surface Preparation

Areas to be paved shall be true to lines and grades shown on the Contract plans and shall have a
properly prepared surface prior to the start of paving operations. Areas to be paved shall be prepared
in compliance with these specifications and the particular specifications.

When an asphaltic concrete pavement course is to be placed on top of an existing pavement, the
existing pavement surface shall be prepared in accordance with Article 3.3.4.2.

Priming or tacking of surfaces to be paved shall be in accordance with 3.4.

Surface of kerbs, vertical faces of existing pavements and all structures in actual contact with asphalt
mixes shall be painted with a thin and complete coating of tack coat, as approved by the Engineer,
to provide a closely bonded, watertight joint.

All openings or structures in the road for water, drainage and other specified utilities shall be
constructed and their positions and levels determined before the start of paving operations.

All utility trenches, cut in the bituminous road surfaces shall be backfilled, compacted and prepared,
all in accordance with Article 3.3.4.2.

3.3.3.5 Preparation of Asphaltic Concrete Mixes

a. Preparation of Asphalt Binder

Asphalt Binder shall be heated to a temperature to yield viscosities in the range of 150-300 mm

/sec.

(75-150 seconds Saybolt-Furol) when delivered to the mixer, as determined from the temperature
viscosity chart of the product used. Asphalt Binder shall not be used if foaming occurs nor shall it
be heated above 177



C at any time.

b. Preparation and Handling of Mineral Aggregate

Coarse and fine aggregate shall be stored at the asphalt plant in such a manner that the separate
stockpiles will not become intermixed. Stockpiles shall be of sufficient size to provide a minimum
quantity of one week's continuous production of asphalt mix. Aggregates brought to the asphalt
plant to supplement stocks should be tested and approved prior to placing in the existing approved
stockpiles.

Cold  bins  shall  be  calibrated  with  the  materials  to  be  used  and  the  settings  shall  be  such  as  to
produce  a  combined  gradation  in  accordance  with  the  job  mix.  Proportioning  shall  be  such  that
surpluses and shortages in the hot bins shall not cause breaks in the continuous operation.  All the
above shall be as approved by the Engineer.

Materials shall be thoroughly dried and heated so that their temperature is within 8



C of the

temperature needed to satisfy the viscosity requirements of the Asphalt Binder. In no case shall the
materials be introduced into the pugmill with a temperature, including the 8



C tolerance permitted,

of more than that at which the Asphalt Binder has a viscosity of 75 seconds Saybolt-Furol. Moisture
content of the heated and dried materials shall not exceed 0.5 %. Quantity of materials fed through
the drier shall in all cases be held to an amount which can be thoroughly dried and heated within the
limits specified.

Heated materials shall be screened into sizes such that they may be combined into a gradation
meeting the requirements of the job mix formula and the hot aggregate storage bins shall be such
as to minimize segregation and loss of temperature of aggregate. Hot bins shall be drawn and
cleaned of material at the end of each day's operation.

c. Proportioning and Mixing

Heated ingredients together with the mineral filler and Asphalt Binder shall be combined in such a
manner so as to produce a mixture which, when emptied from the pugmill, complies with the
requirements of the job mix formula. Plant settings, once established, shall not be changed without
the approval of the Engineer.

Temperature of the aggregate immediately prior to mixing shall be within ±8



C of the temperature

of  the  Asphalt  Binder  and  the  temperature  of  the  aggregate  and  asphalt  prior  to  mixing  shall  be
approximately that of the completed mix as defined in the job mix formula approved by the Engineer.
Mix temperature shall be within the limits set out in the job mix formula when emptied from the mixer

Mineral filler in a cold dry state shall be proportioned into the mixer either with the aggregate or after
the introduction of the Asphalt Binder to avoid loss of filler that may occur in dry mixing as a result of
turbulence in the mixer.

When anti-stripping additive is required, the additive device shall be calibrated and set so that the
specified amount of anti-stripping additive is thoroughly mixed with the bitumen just prior to entering
the pugmill.

d. Control of Mixing Time

In a batch type plant, the Engineer will designate the length of time of both dry and set mixing periods
to ensure a uniformly and completely coated mix.  Mixing period time shall not be altered unless so
ordered by the Engineer.  A dry mixing period of not less than four seconds shall precede the addition
of the Asphalt Binder to the mix. Excess wet mixing shall be avoided.  Wet mixing shall continue as
long as is necessary to obtain a thoroughly blended mix but shall not exceed 75 seconds nor be less
than 40 seconds.

In continuous type plants, the weights shall be determined for the job from tests made under the
supervision of the Engineer and the determination of mixing time shall be by the weight, unless
otherwise required:

Mixing time, sec. =

Pugmill dead capacity, kg

Pugmill output, kg per sec.

Equation 3-1: Mixing Time

Maximum mixing time in batch or continuous type plants shall be limited as directed by the Engineer
to avoid undue changes in the characteristics of the asphalt material.

3.3.3.6 Delivery of the Asphaltic Concrete Mixes

Dispatching of the hauling vehicles to the job site shall be so scheduled that all material delivered
may be placed in daylight, unless the Engineer approves the use of artificial light. Delivery of material
shall be at a uniform rate and in an amount well within the capacity of the paving and compacting
equipment.

The mix shall be delivered to the paver at a temperature determined from the temperature-viscosity
curve.

All precautions shall be taken to protect the mix from the weather.

3.3.3.7 Spreading and Finishing

a. General

Spreading and finishing equipment complying with Article 3.3.3.1 shall be used.  Mix shall be laid
upon an approved surface in accordance with the specifications and only when weather conditions
are suitable.  Upon arrival at the point of use, the asphalt mix shall be spread and struck off to the
grade, elevation and cross-section shape intended, either over the entire width or over such partial
width as may be required. If the mix does not comply with the requirements, it shall not be used but
shall be discarded. All bituminous mixes shall be introduced to the paver at a temperature not less
than  135  deg.  C  and  not  more  than  163  deg.  C.  Mixes  outside  this  temperature  range  shall  be
discarded.

Asphalt course shall be constructed to proposed levels and shall be homogeneous and providing,
after compaction, an even surface free from undulations, rises or depressions, and within the
tolerances stipulated. In no case shall construction of a new asphaltic concrete course begin until
the previously laid course has been tested and approved in accordance with these specifications.

Asphalt course shall be laid in more than one layer, with no layer exceeding 100 mm in thickness
unless otherwise shown on the Contract plans or approved by the Engineer. Bitumen mixtures
except on levelling course shall be spread in a placement thickness so that, after rolling the normal
thickness of the compacted bituminous material shall be:

•

Base Course:

Min. 6 cm.

Max. 10 cm.

•

Binder Course:

Min. 5 cm.

Max. 8 cm.

•

Wearing Course:

Min. 4 cm.

Max. 6 cm.

Where successive layers are to be placed, second layer shall be placed as soon as practicable after
the first layer has been finished, rolled and cooled. Unless otherwise directed by the Engineer, the
surface of the existing layer shall be cleaned and a thin tack coat will be applied.

Transverse joints in succeeding layers shall be offset at least 2 m. Longitudinal joints shall be offset
at least 150 mm. All joints shall be a minimum of 150 mm from all pavement markings.

Use of motor graders or hand spreading of the asphalt mix shall not be permitted except in places
where it is impractical to use pavers and shall be only with the specific permission of the Engineer.
This shall be to avoid segregation of the asphalt mix and shall comply with all conditions regarding
trueness of level, thickness and homogeneity of the mix.

Automatic screed controls shall be required on all pavers and shall be used for paving courses as
approved by the Engineer.

b. Preliminary Survey and Reference String Line

The Contractor shall make the survey required for the reference grade. When the survey is approved
by  the  Engineer,  the  Contractor  shall  erect  and  maintain  an  approved  reference  string  line  and
operate the paver to conform to the string line for the initial layer and/or any other layers as directed.
Elevation  control  point  stakes  for  the  first  layer  of  bituminous  paving  course  shall  be  set  at  a
maximum spacing of twenty (20) metres. For subsequent layer, control point shall be set at ten (10)
metres maximum spacing. The Contractor shall furnish and maintain an approved mobile string line
for  all  layers  not  laid  with  the  erected  string  line.  The  string  line  shall  be  erected  parallel  to  the
reference grade, and the bituminous mixture shall be spread at a constant elevation above, below
or at the string line elevation as directed.

The use of the automatically controlled bituminous paver, to provide both longitudinal and transverse
control, shall include the furnishing and maintaining of a string line, whether it be erected or mobile,
by the Contractor. The longitudinal and transverse controls shall operate independent of each other,
to the extent that the surface of the bituminous mixture will conform to the string line and will be
uniform in cross-section or crown.

The Contractor shall establish the centreline points and shall maintain the location of the points until
the completion of the surfacing or as directed. When directed by the Engineer, the Contractor shall
erect a string line, to be used as a guide for the finishing machine, in order to maintain a uniform
edge alignment. If any other method is proposed by the Contractor, it shall be approved by the
Engineer.

c. Machine Spreading

The  Contractor  shall make  a  survey  of  the  centreline  profile  and  crown of  the  existing  surface  or
base  and  determine  or  calculate  a  Reference  Grade  Line  and  shall  furnish  to  the  Engineer  for
reference and approval the full values at each profile point necessary to erect the Reference String
Line.

On the initial traffic lane paving operation, the asphaltic mixture shall be spread with the bituminous
paver to a grade line constant to the Reference String Line.

The erection and maintenance of the Reference String Line shall be so coordinated that the string
will be taut and free from sags at the time it is in use as a guide for the paver.

On the second and subsequent layers, the asphaltic mixture shall be spread as described for the
initial layer except that the spreading of the asphalt shall conform to a Mobile String Line.

The Mobile String Line or equivalent shall be used as the reference guide on all paving operations,
except when the Reference String Line is used or other provisions are made and approved by the
Engineer.

On new construction, where paving starts on fresh earth subgrade, the survey may, if approved by
the Engineer, be delayed to the surface of the first layer and the use of the Reference Grade Line
may be delayed to the first lay- down operation of the second course.

If the existing surface is one of acceptable centreline grade, as determined by the Engineer from the
Contractor's profile survey, the Engineer may permit the use of the mobile String Line for all layers.

No mixture shall be placed prior to the Engineer's approval of the Contractor's proposed methods
and procedures for placing the mixture.

d. Levelling Course

A levelling course, consisting of a layer of bituminous material of variable thickness may be used to
eliminate irregularities in existing surfaces or based and to vary existing cross-section elements of
roadways.

In areas where levelling courses are required, as determined by the Engineer, the Contractor shall
make survey of the existing surface or base. When the survey is approved, the Engineer will
determine and inform the Contractor of the precise locations and thicknesses of levelling course to
obtain the smoothest possible riding surface. Upon receipt of the locations and thicknesses from the
Engineer, the Contractor shall proceed with the placement of the "Levelling Course".

3.3.3.8 Compaction

Compaction Temperature must be checked against appropriate values determined from
Temperature-Viscosity Curves.

Rolling  equipment  for  use  in  compacting  asphalt  mixes  shall  meet  the  requirements  of  section
3.3.3.1.c.  At least three rollers shall be required at all times:  one self-propelled pneumatic-tired and
two steel-wheeled rollers.  As many additional rollers shall be used as necessary to provide specified
asphalt course density and surface characteristics in an orderly, efficient and continuous manner.

Immediately after the asphalt mix has been spread and struck off, the surface shall be checked and
any irregularities adjusted and then compacted thoroughly and uniformly by rolling.

To prevent adhesion of the mix to steel-wheeled rollers, the wheels shall be kept properly moistened
but excess water will not be permitted by the Engineer.

After the longitudinal joints and edges have been compacted, rolling shall start longitudinally at the
sides  of  the  road  and  shall  gradually  progress  towards  the  center.    On  super-elevated  sections,
rolling shall begin on the low side and progress to the high side, overlapping on successive trips by
at  least  one-half  the  width  of tandem rollers  and  uniformly  lapping  each preceding track.   Rollers
shall move at a slow but uniform speed with the drive wheels nearest the paver.  Speed shall not
exceed 4.8 km/hr. for steel-wheeled rollers or 8.0 km/hr. for pneumatic-tired rollers. Operating speed
shall be approved by the Engineer.

Line of rolling shall not be changed suddenly or the direction of rolling reversed suddenly. If rolling
causes displacement of the material, the affected areas shall be loosened at once with hand tools
and restored to the original grade of the loose material before being re-rolled. Heavy equipment or
rollers shall not be permitted to stand on the finished surface before it has been compacted and has
thoroughly cooled.

When paving in a single width, the first lane placed shall be rolled in the following order:

1. Transverse joints

2. Longitudinal joints

3. Outside edge

4. Initial or breakdown rolling, beginning on the low side and progressing towards the high side

5. Second rolling

6. Finish rolling

When paving in echelon, five to ten centimeters of the edge which the second paver is following shall
be left unrolled. Edges shall not be exposed more than fifteen minutes without being rolled.
Particular attention shall be given to the construction of the transverse and longitudinal joints in all
courses.

a. Transverse Joints

Transverse joints shall be carefully constructed and thoroughly compacted to provide a smooth riding
surface.    Joints  shall  be  checked  with  a  straight-edge  to  assure  smoothness  and  true  alignment.
Joints shall be formed with a bulkhead, such as a board, to provide a straight line and vertical face.
If the joint has been distorted by traffic or by other means, it shall be trimmed to line and the face
shall be painted with a thin coating of emulsified asphalt before the fresh material is placed against
it.  To obtain thorough compaction of these joints, the material placed against the joint shall be tightly
pushed against the vertical face with a steel-wheeled roller.  Roller shall be placed on the previously
compacted material transversely so that not more than 150 mm of the rear rolling wheel rides on the
edge of the joint. Roller shall be operated to pinch and press the mix into place at the transverse
joint.  Roller shall continue to roll along this line, shifting its position gradually across the joint, in 150
to 200 mm increments, until the joint has been rolled with the entire width of the roller wheel.  Rolling
shall be continued until a thoroughly compacted, neat joint is obtained more than 150 mm of the rear
rolling wheel rides on the edge of the joint. Roller shall be operated to pinch and press the mix into
place at the transverse joint.  Roller shall continue to roll along this line, shifting its position gradually
across the joint, in 150 to 200 mm increments, until the joint has been rolled with the entire width of
the roller wheel.  Rolling shall be continued until a thoroughly compacted, neat joint is obtained.

b. Longitudinal Joints

Longitudinal joints shall be rolled directly behind the paving operations.  First lane placed shall be
true to line and grade and have a vertical face.  Material being placed in the abutting lane shall then
be tightly pushed against the face of the previously placed lane.  Before rolling, the coarse aggregate
in the material overlapping the joint shall be carefully removed with a rake and discarded.  Rolling
shall be performed with a steel-wheeled roller.

Roller  shall be shifted over  onto the previously placed lane so that not more than 150 mm of the
roller wheel rides on the edges of the newly laid lane.  Rollers shall then be operated to pinch and
press  the  fine  material  gradually  across  the  joint.    Rolling  shall  be  continued  until  a  thoroughly
compacted, neat joint is obtained.

When the abutting lane is not placed in the same day, or the joint is distorted during the day's work
by traffic or by other means, the edge of the lane shall be carefully trimmed to line, cleaned and
painted with a thin coating of emulsified asphalt before the abutting lane is placed.

c. Edges

Edges of the asphalt course shall be rolled concurrently with or immediately after rolling the
longitudinal joint.

Care shall be exercised in consolidating the course along the entire length of the edges. Before it is
compacted, the material along the unsupported edges shall be slightly elevated with hand tools. This
will permit the full weight of the roller wheel to bear on the material to the extreme edges of the mat.

d. Breakdown Rolling

Breakdown rolling shall immediately follow the rolling of the longitudinal joints and edges. Rollers
shall be operated as close to the paver as possible to obtain adequate density without causing undue
displacement. In no case shall the mix temperature be allowed to drop below 110



C prior to

breakdown rolling. If it is so happens, such areas shall be identified on site, removed from the
permanent work and replaced with approved mix complying with all applicable requirements. If the
breakdown roller is steel-wheeled, it shall be operated with the drive wheel nearest the finishing
machine. Pneumatic-tired rollers may be used as breakdown rollers.

e. Intermediate Rolling

Pneumatic-tired  rollers  or  steel-wheeled  rollers  described  in  c)  shall  be  used  for  the  intermediate
rolling. Intermediate rolling shall follow the breakdown rolling as closely as possible and while the
paving mix is still of a temperature that will result in maximum density from this operation.  Rollers
shall  be  used  continuously  after  the  initial  rolling  until  all  of  the  mix  placed  has  been  thoroughly
compacted.  Turning of rollers on the hot paving mix which causes undue displacement will not be
permitted by the Engineer.

f. Finish Rolling

Finished rolling shall be accomplished while the material is still warm enough for the removal of roller
marks.

All rolling operations shall be conducted in close sequence.

In places inaccessible for the operation of standard rollers as specified, compaction shall be
performed by manual or mechanical tampers of such design as to give the desired density.

After final rolling, the smoothness, levels, cross falls, density and thickness shall be checked and
any irregularity of the surface exceeding the specified limits and any areas defective in texture,
density or composition shall be corrected as directed by the Engineer, including removal and
replacement at the Contractor's expense as directed by the Engineer.

3.3.3.9 Protection of the Asphalt Courses

Sections of the newly finished work shall be protected from traffic of any kind until the mix has been
properly compacted and cooled to ambient temperature. In no case shall traffic be permitted less
than 12 hours after completion of the asphalt course unless a shorter period is authorized by the
Engineer.

3.3.3.10

Testing and Acceptance of Completed Asphaltic Concrete

Courses

Each completed asphalt concrete course shall be tested and approved in accordance with the
following requirements prior to placing any subsequent asphalt concrete course.

Contractor shall, at his own expense, cut samples from each completed asphalt course during the
progress  of  the  work  and  before  final  acceptance  of  the  project,  all  as  directed  by  the  Engineer.
Compacted samples shall be taken by coring in accordance with AASHTO T-230, for testing by the
Engineer.  Where the Contractor fails to provide cores as required by the Engineer, the Engineer
may  arrange  for  the  taking  of  cores  at  the  Contractor's  expense.    Samples  shall  be  taken  of  the
asphalt mix for the full depth of the course from the location directed by the Engineer at a rate of not
less than one sample per 200 linear meters of road.

Whenever deficiencies are noted in loose mix samples or core samples, the Engineer may direct the
taking of additional cores at the Contractor's expense in order to define the area of pavement
involved.

Hot asphalt mix shall be placed and compacted in holes left by sampling.

a. Requirements for compaction of asphalt concrete courses

Degree of compaction is the ratio of the specific gravity of the pavement sample to the specific gravity
of the laboratory Marshall specimens prepared in accordance with the job mix formula.

Minimum degree of compaction required for the various types of asphalt concrete, expressed as a
percentage, shall meet the requirements of Table 3-36.

Table 3-36: Minimum degree of required compaction

Type of Mix

Minimum degree of compaction

required

Base Course

98 %

Binder Course

98 %

Wearing Course

98 %

In the event the specific gravity of samples cut from any asphalt concrete course fail to comply with
the minimum required, this will be considered a major defect in the work on the basis of which the
portion of the asphalt course represented by these samples shall be rejected.

Degree of compaction in excess of 101.5% shall not be permitted. The specific gravity of compacted
asphalt cores shall be measured in accordance with ASTM D 2726/AASHTO T-230.

Degree of compaction for all asphalt layers with respect to maximum theoretical Specific
gravity shall be calculated and documented.

b. Requirements for Air Voids, Asphalt Content and Gradation

Samples of the mixed materials shall be taken from the first two hundred tones and from every two
hundred  tones  thereafter  to  determine  aggregate  grading  and  binder  content.  Samples  of  loose
asphaltic concrete mix shall be taken behind the paver before compaction and shall be obtained in
accordance  with,  ASTM  D-979.  Samples  of  compacted  asphaltic  concrete  shall  be  obtained  by
coring in accordance with Method B of AASHTO T-230.

If the grading of the mix falls outside of the Job Mix Limit (JML) the second part of the mix shall be
checked. If the average grading indicate a maximum of three (3) sieves out of JML by maximum 1%
or a maximum of two (2) sieves out of JML by maximum 2% the material shall be accepted in the
permanent works when an additional one year guarantee shall be provided by the contractor on
condition that the laid mix meet all other aspects of the specification. However, if it so happens twice
within 15

days’ time, the works shall be suspended, hot bin samples re-cheeked and adjustment

made in the plant and if required re-designed.

Determination  of  bitumen  content  and  extraction  gradation  may  be  performed  on  either  loose  or
compacted samples in accordance with AASHTO T-164 and AASHTO T-30 except that the mass of
mineral matter in the total volume of the extract shall be determined by using a bitumen meter or
other  equipment  and  procedures  which  give  equally  satisfactory  results.  The  specific  gravity  of
compacted  asphalt  course  shall  be  measured  in  accordance  with  AASHTO  T-230.  Gmm  as  per
ASTM D-2041shall be checked on daily bases and used for calculating air voids.

If any of these tests show results which are not in accordance with approved job standard mix within
permissible variations the material shall be rejected and suitable adjustments shall immediately be
made to ensure compliance therewith. Samples of the mixed material shall be taken at least twice a
day or as determined by the Engineer for making Marshall Specimens to determine stability, flow
and unit weight. For the samples to be taken for the making of daily Marshall Specimens the mixing
pug mill temperature shall be set to the mixing temperature as specified in AASHTO T-245 and the
compaction temperature of the moulds shall also be in accordance with AASHTO T-245.  Should for
practical reasons the pug mill temperature be different from that used in AASHTO T-245 then the
Engineer  shall  set  the  compaction  temperatures  for  the  moulds  to  so  compensate.  All  approved
sampling  and  testing  required  under  the  sub-clause  of  this  clause  shall  be  undertaken  by  the

Engineer. Sampling and testing by the Engineer in no way relives the Contractor of his responsibility
for regular quality control testing in order to ensure compliance with the Specifications.

If the Marshall stability of the mix is found a maximum of 200 kgf less than the minimum specified
requirement, fresh hot bin samples shall be taken and six Marshall Specimens made on the average
grading and bitumen content of the production date. If the stability is found satisfactory the material
laid on site shall be accepted without any deduction. If not, the material shall be removed and
replaced at contractor’s cost.

The density of the compacted mixes shall be related to the daily Marshall Density, which shall be
determined by taking the average of four standard Marshall specimens made from samples of the
mix taken from the mixing plant or paver. The density of each sample shall be determined and
compared with the mean value. Any individual result which varies from the mean by more than 0.015
gm/cc shall be rejected. Marshall tests shall be repeated on a daily basis to establish the daily
Marshal Density for that particular day's production. The daily Marshall Density shall not vary from
the job mix Design Density by more than + 0.75%. If it does, the higher of the densities (daily Marshall
Density or Job Standard Density) shall be applied to satisfy the requirements of in-situ compaction.
However, the in-situ air voids shall not be less than 4.5% and more than 8.5% if it so happens the
matter shall be investigated. In the event of recurrent the hot bin samples shall be immediately taken,
the specific gravity rechecked and the situation rectified

– if needed the mix redesigned.

The “Job Standard Mixture Reference Density” (JSMD) shall be obtained by making six standard
Marshall Specime

ns from samples of the approved “Job Standard Mixture” determining the relative

density or each and comparing them with the mean values of the six. Any individual result which
differs from the mean by more than 0.015 gm/cc shall be rejected and provided not more than two
results are so rejected the mean of the remaining results shall be designated the “Job Standard
Mixture Reference Density”. Generally the average density of the specimens made for checking the
loss of stability of the mix shall be taken as JSMD unless otherwise directed by the Engineer.

In the event it transpires from the analysis conducted on samples of loose mix or cores that the
asphalt content or aggregate gradation are beyond the permissible tolerances specified for the job
mix formula established for each respective asphalt course mix, as determined by the Engineer,
such variation affects the characteristics of the asphalt mix as far as its compliance with the Contract
conditions and specifications is concerned, this shall be considered a major defect in the work on
the basis of which the portion of the asphalt course represented by these samples shall be rejected.

c. Requirements for Thickness

Total constructed thickness of asphaltic concrete base course or asphaltic concrete wearing course
used for new construction, reconstruction or roadway widening shall not vary more than 6 mm from
the total thickness shown on the Contract plans and included in the bills of quantities.

In the event the constructed thickness of the asphaltic concrete base course or asphaltic concrete
wearing course is 6 mm more than the total thickness shown on the Contract plans, the area shall
be corrected as directed by the Engineer by removing the excess material in an approved manner
to provide the required thickness.

In the event the constructed thickness of the asphaltic concrete base course or asphaltic concrete
wearing course is 6 mm less than the total thickness shown on the Contract plans, the Contractor
shall provide additional material in the next course (base course or wearing course). In no case shall
the deficiency of the base course exceed 12 mm and in no case shall the deficiency of the wearing
course exceed 8 mm. In the event the total thickness of the wearing course is less than the total
thickness required by the Contract plans by more than 6 mm, the Contractor shall remove the top
layer of 50 mm or to a depth as directed by the Engineer and a new layer constructed so the total
thickness of the wearing course is within the limits indicated on the Contract plans and as specified
herein.

Asphaltic concrete base course and the asphaltic concrete wearing course shall be constructed to
the grade level as shown on the Contract plans, as specified and as approved by the Engineer.

In no case shall the total sum thickness of the subbase, base course and wearing course be less
than the total sum thickness of all courses shown on the Contract plans.

Tolerances specified herein shall not invalidate the tolerances set forth for the evenness of surfaces
of the asphaltic concrete courses.

d. Requirements for Evenness of Surface

Engineer shall test the evenness of surface for each course of the various asphalt concrete courses
incorporated in the Contract to ascertain their compliance with the conditions, these specifications
and the Contract plans with regard to levels, longitudinal falls, cross-sections and evenness of
surface.

Contractor shall put at the disposal of the Engineer a five-meter straight-edge and a crown template
of sturdy construction and approved design and enough labor to assist in the checking operations.

Any layer containing deviations or variations exceeding the following tolerances shall be corrected
or removed and replaced, at the expense of the Contractor, to the satisfaction of the Engineer and
according to the following specifications:

1. Variation in the levels of the profile grade line after construction shall not exceed one

centimeter from the levels indicated on the Contract plans.

2. When tested by a five-meter straight-edge placed at right angle and parallel to the road

centerline at intervals not exceeding two meters, or when tested by a crown template placed
at right angle to the road centerline at intervals not exceeding half the template length,
variation of the surface of the road from the testing edge between any two contacts with the
surface shall not exceed the following maximum tolerances:

Base Course: 6 mm

ii.

Wearing Course: 4 mm

Tolerances herein specified for evenness of surface shall not invalidate the tolerances set
forth for thickness of the asphalt concrete courses.

3. In no case shall the final surface of the roadway be constructed such that surface water will

stand on the roadway in depths exceeding the above maximum tolerances.

4. The rideability of the completed final wearing course, or other desired surface courses, shall

be tested using laser road surface profile measurement equipment complying with the latest
edition of ASTM E950, Class 1 device (or other equivalent and internationally recognized
standard). The device shall measure both wheel paths with laser height sensing instruments
and it shall have a valid calibration certificate.

The IRI shall be computed according to the latest edition of ASTM E1926 (or other equivalent
and internationally recognized standard) from the longitudinal profile measurements of the
road surface

5. Rideability of the finished wearing course when tested with a laser road surface testing

machine shall have an International roughness index not exceeding the following values:

Average value over a 400 m section

For posted speed ≥ 100 km/hr: ≤ 0.90

b) For posted speed 80 km

/hr: ≤ 1.10

For posted speed 60 km/hr: ≤ 1.30

For posted speed < 60 km/hr: ≤ 1.50

ii.

Peak value over a 25 m section: ≤ 1.5 (not more than 2 values per 400 meters)

All humps and depressions exceeding the specified tolerance shall be corrected by removing the
defective work and placing it with new material as directed by the Engineer at the Contractors cost.

Abu Dhabi, United Arab Emirates. STANDARD CONSTRUCTION SPECIFICATIONS (PART 1 - ROADS, Second Edition 2020) - page 37