2. 2
Learning Outcomes
At the end of the lecture, students should be
able to:
Explain the process of asphalt concrete
pavement construction
3. Important Factors that Influence Asphalt Pavement
Construction Process
Ensure paving with a minimum number of transverse joints
The reference point for screed operation should not be readjusted too
much-avoid constant/frequent readjustments of the paver’s automatic
controls
Use proper guideline to select the correct rolling techniques-types and
number of rollers, number of passes and rolling pattern
Make sure that the equipment such as paver and rollers is in good
operating condition
During laydown or rolling, if a problem is identified as a material or mix
design related problem, then it must be reported to the lab/plant as
quickly as possible to ensure readjustments or corrective actions
4. Pavement Potential Problems and Solutions
Material
Selection
Bleeding: check type of filler, grade of binder
Brown streaks: avoid highly absorptive aggregates, check quality of
binder
Checking under roller, tender mix, check quality of binder and
temperature
Mix design Bleeding, poor quality longitudinal joints: check amount of filler,
VMA and binder content, voids and lab compaction procedures
Tender mix and checking under roller: check filler and binder
content, binder temperature-viscosity characteristics
Segregation: check gradation
Transverse cracks: check binder content, filler content and binder-
temp viscosity
Lean, brown dull appearance of surface: check filler content
Poor compaction: check for binder content
Storage Bleeding: check stockpiling and drying techniques
Segregation: check stockpiling
5. Pavement Potential Problems and Solutions
Plant
production
Bleeding or lean brown, dull appearance of surface: check
fuel/burner/nozzles
Segregation: check storage bins
Checking under roller: check mix temperature
Poor compaction or wavy surface: check mix temperature, binder
viscosity-temp characteristics, binder properties
Tack/prime
coating
Bleeding, transverse cracks or shoving of material ahead of roller:
check type and application rates and time available for curing of
emulsion and penetration of prime coat into granular layers
Transportation Bleeding: check release agents on truck beds
Poor quality, lean brown dull appearance or surface, uneven
thickness and quality or poor compaction: check insulation in
trucks
Wavy surface: check for brakes in truck
Lift thickness Checking under roller, shoving of material ahead of roller, tearing
of material or poor compaction: check proper lift thickness
6. Potential Problems and Solutions
Transfer Segregation or poor quality longitudinal/transverse joint: check for
temperature variation across material consider using MTD
Paving Bleeding or segregateion: check paver speed and different parts such
as auger and screed and mix in hopper
Checking under roller, depression or poor quality longitudinal cracks:
check screed
Poor quality longitudinal/transverse cracking: check screed, hopper
and feed and sensor
Tearing of material: check paver speed and screed, feeder gate
Uneven thickness and quality or wavy surface: check hopper gates,
conveyor and spreading screw, sensor, auger and screed pull point
Rolling Bleeding: check rolling pattern and number of passes
Tender mix: change type of roller
Checking under roller: check roller pattern, speed and number of
rollers
Poor quality: check number and speed of rollers and rolling direction
Poor compaction: check for number, type and speed of rollers,
frequency of vibrations and pressure in tyres of rubber tyred roller
8. SURVEY AND ALIGNMENT
Involve measurement of angle, distance and height maps,
contour and other related drawings
Reconnaissance survey of the entire area – planning (aerial photo)
Reconnaissance survey of feasible route - planning
Location survey and site setting out – setting out points on site
according to drawings e.g ROW, alignment, CL, leveling, etc.
Preliminary survey of the best route - data used to produce map,
plans, section drawings, etc.
1
10. SITE CLEARING
Initial process in road construction works and preventing the
occurrence of obstacles during construction works
2
CLEARING
GRUBBING
STRIPPING OF
TOPSOIL
11. Construction Machinery Involved in Site Clearing
Types of Machinery Functions
Chainsaw Cutting down timber
Hydraulic excavator
Site excavating
Backhoe
Bulldozer Disposal and levelling of site
Trucks Transporting purposes
12. Consist of excavation, backfill, transportation, stockpiling, spreading,
compaction, forming embankment and slopes, etc as is necessary up
to the formation levels.
Tests conducted on soil, if found to be unsuitable (e.g. organic, marine
clay) need to be treated, remove and replaced with suitable material
Provide temporary water course, ditches, drains, pumps and silt trap to
maintains earthworks free from water.
EARTHWORK
3
The purpose of earthworks is to level the ground to the required level
(either road finished level or at-least 200 mm higher than road formation level)
which bound to be the subgrade of the pavement.
14. EARTHWORK - Compactor
Smooth wheel – compaction by
dead weight, additional pressure
(ballasted with water/sand),
vibrate, for granular and premix
Pneumatic – 12 > 200 ton, for
cohesive, sandy soil, premix,
surface dressing
Vibratory – rearrange soil grains
through vibration, suitable for
coarse grained soil
Sheep foot – compact from bottom
upwards, 3 > 27 ton, for clay, silt,
fine grained soil
15. 3) EARTHWORK - Turfing
Protective Vegetation
(Erosion Control)
Topsoil spread and lightly
compacted, thickness 50mm
Block 250 x 250 mm, free of
lallang and weeds
Slope steeper than 1:3,
pegged with bamboo stakes
Seeding/hydroseeding –
submit 4 weeks in advance
with proposed method and
material
All turf shall be regularly
watered and fertilised
Dead turf to be replaced
with new turf
EARTHWORK - Turfing
16. DRAINAGE WORK
4
Surface Drainage
Road surface has to be free of standing
water, drains water away to side drains
down to open water course.
Sub Surface Drainage
To handle ground water so that the level
is low enough, avoiding soil from
becoming plastic
Culvert
Either precast box, PVC, corrugated metal
pipe or reinforced concrete may be used
depending on the drawings. Material
required depends on type of culvert used
and shall meets the specification
17. Generally defined as a structure of wood, stone, brick, steel, concrete or
composite that provides a passage across a gap such as river, railway, roadway
or etc, without closing the way beneath the gap.
BRIDGE WORK
5
18. • Preparation
Of The
Subgrade
• Preparation
Of The
Subbase
• Preparation
Of The Road
Base
• Coating
• Surfacing
Road Layer
Subbase
Subgrade
Base
Surface course
PAVEMENT WORK
6
19. SUBGRADE
Compaction – The subgrade must be
compacted to adequate density to avoid
compression after construction which may
cause the pavement to deform.
Stabilization – this can be done by adding
lime, cement or emulsified asphalt mixed
with subgrade soil to improve the stiffness
and strength of subgrade. Geotextiles can
also be use to stabilize the subgrade.
Over-excavation – this process is the
removal and replacement of poor subgrade
soil and replaced with quality soil
To prepare the subgrade, the surface
must be excavated, scarified, levelled
and compacted to the required level
20. Then, subbase material either
sand, laterite, crushed aggregate
or cement stabilized is laid and
compacted to the required
thickness.
Steel cylinder roller is used to
compact the subbase layer to not
less than 95% of the maximum dry
density determined in Compaction
Test in laboratory as per JKR
Standard Specification for Road
Works (JKR/SPJ/1988).
Material requirements:
natural or crushed aggregate
liquid limit not greater than 25%
Plasticity index not greater than 6
ACV not greater than 35
Minimum CBR of 30% when
compacted to 95% of MDD under 4
days soaked condition.
SUBBASE
21. Following that, the laying of
base course layer that may
be consisted of dense
bituminous macadam,
cement stabilized or a
stabilized crushed aggregate
is similar to that of subbase
layer by aggregate spreader.
It needs to be compacted
also to 95% maximum dry
density.
Material requirements:
Natural or crushed aggregate , Plasticity
index not greater than 6, ACV not greater
than 30
Minimum CBR of 80% when compacted to
95% of MDD under 4 days soaked condition
Flakiness Index not greater than 30
Not less than 80% of particles retained on
the B.S 4.75 sieve shall have at least one
fractured surface
Sodium Sulphate Test not greater than
12%
Gradation
ROAD BASE
22. COATING - Prior to laying of binder course
to base course, a thin layer of prime coat is
sprayed onto the cleaned base course
surface in order to enhance the bonding
between binder course (bituminous layer)
and base course (non-bituminous layer).
PAVEMENT WORK - COATING
7
The bituminous priming material shall be
either cut-back bitumen or bitumen
emulsion. Cut-back bitumen shall be grade
RC-70 or MC-70 conforming to the
requirements of M.S. 159.
Bitumen emulsion shall be slow setting,
grade SS-1 or SS-1K, conforming to the
requirements of M.S. 161.
The rate of application usually is in the
range 0.5 to 1.0 litre/sq.m.
Prime coat shall normally be left
undisturbed for at least 24 hours after
application.
23. SURFACING - The premixed asphalt, namely binder course are then transported to
the construction site and laid to the base course layer by pavers and then compact
mechanically by rolling.
Material requirements:
Water absorption not greater than 2%
Plasticity index not greater than 6
ACV not greater than 30
Minimum CBR of 80% when compacted to 95% of MDD under 4 days soaked
condition
Flakiness Index not greater than 30
Sodium Sulphate Test not greater than 12%
Gradation
PAVEMENT WORK - SURFACING
8
25. Initial rolling – smooth wheel, <5 km/h
Intermediate Rolling – rubber tyre, < 8 km/h,
weight > 15 tonne, tyre pressure > 0.7 N/m2
Finish Rolling – smooth wheel
Open to traffic > 4 hours, < 30 km/h
Pavement Work - Rolling Pavement Work - Coring
Core Samples
diameter 100mm each sample
500 m2
26. PAVEMENT WORK – Finishing
Guard rail Traffic signs
Road markings
Street lightings
Traffic signal
27. Summary of Content
•The important steps in asphalt pavement construction consist of
selection of materials, proper mix design, transportation, laydown
and good monitoring and quality control during construction of
the pavement.
•Proper equipment and construction procedure is important to
ensure quality and durable pavement during its service life
28. 1. Roberts, Kandhal, Brown, Lee & Kennedy, (2009). Hot
Mix Asphalt Materials, Mixture Design and
Construction, 3rd Edition, NAPA Education and
Research Foundation.
2. Rajib B. Mallick and Tahar El-Korchi. (2009).
Pavement Engineering, Principles and Practice, CRC
Press
3. Nick Thom (2008). Principles of Pavement
Engineering, Thomas Telford
References
&
Acknowledgement
29. BIODATA
Name : Assoc. Prof. Dr. Juraidah Ahmad
Email : juraidah@salam.uitm.edu.my
Faculty : Faculty of Civil Engineering
Name : Assoc. Prof. Ir. Dr. Ahmad Kamil Arshad
Email : drahmadkamil@salam.uitm.edu.my
Faculty : Faculty of Civil Engineering
Name : Dr. Ekarizan Shaffie
Email : eka@salam.uitm.edu.my
Faculty : Faculty of Civil Engineering
