Please enable JavaScript.
Coggle requires JavaScript to display documents.
Construction of Road Layers ( Pavement Work) (6. Compaction (Consists of…
Construction of Road Layers ( Pavement Work)
Carried out after the
survey
,
alignment works
,
site-clearing
,
earthwork
and
temporary drain
has completed.
1. Drainage Layer
Laid on
prepared
and
acceptable
subgrade
Coarse and Fine
aggregates are used.
Laid and compacted at
moisture content of between +1% - -2%
of optimum moisture content.
2. Subbase
Consists of natural/artificial
mixture of sand, gravel, aggregates and free from unwanted organic substances.
Laid at
100 - 200mm
compacted thickness and at
moisture content of between +1% - -2%
of optimum moisture content.
Compaction should produce
density of >=95% of maximum dry density
.
3. Road base
Consists of
gravel, rock and mixture of rock and gravel
Mixture is spread with
motor grader
and having
optimum moisture content of +-1% and laid in 100-200mm
.
Compaction should produce the
same density as the subbase
.
5. Surfacing
Binder Course
will be laid o road base.
Carried out in
dried weather
.
After binder course is compacted,
wearing course
will be laid and compacted.
4. Coating
Prime Coat
contain
liquid bitumen
that is sprayed at rate of
0.5 - 1L/m2.
Tack Coat
contain bitumen emulsion and sprayed onto bituminous layer at rate of
0.25 - 0.55L/m2
Carried out in
dry weather,
Brooming
is carried out to prevent the dust from the soil to fail the coating process.
No vehicles
are allowed to pass through while this process is carried out.
6. Compaction
Consists of
breakdown compaction, principal compaction and final compaction
Machine must operated in
longitudinal direction
Overlapped width must be half of the width of the tires of the machine.
Heavy rollers
should not be parked
on newly laid mix before compacted completed.
The
density, thickness and quality
should be tested.
JKR Compaction Requirement
is
90% ( Road Base ), 95% (Binder Course) and 98% (wearing course)
.
**7. Shoulder
Consists of
furnishing, compacting and shaping the shoulder.
Thickness should be
based on drawing.
Top level of shoulder
should be
levelled and flushed with pavement and also uniformly free draining