different types of machinery used in Bituminous road construction

1. Subject: Advance construction technology (3350605)
Topic: Equipments and machineries used for
bituminous road

2. Sr. no. Name Enrollment
no.
1 Bhavesh hathila 156300306047

3. Index
Batch type hot mixing plant
Paver
Roller
 Smooth wheel rollers
 Pneumatic rollers
 Sheep foot rollers

4. Equipments used for bituminous roads are:
1. Batch type hot mix plant
2. Paver

5. 1.Batch type hot mix plant:

6. Hot mixed asphalt is produced at a central plant
and transported to the paving by trucks. An asphalt plant is
a high tech group of machines, capable of uniformly
blending and mixing the aggregates and asphalt cement
and asphalt concrete.
 Primary components in the order of matter flow are:
1. Cold feed system – feed belt, automatic feeder
2. cold elevator
3. Drum dryer
4. Hot elevator
5. Asphalt handling system
6. Weight hopper
7. Pug mill mixer
8. Surge silo

7. cold feed bins provide aggregate surge storage and
uniform flow of properly sized material for mixing, the cold
feed system consist of three to six open top bins mounted
together as a single unit.
The invidual bins can be feed from sized aggregates
stockpiles by front and loader, clamshell or conveyor.
At the bottom of each bin is a gate of controlling
material flow. Belt conveyor are the most common
equipment for transporting the aggregates from the cold bins
to the drum dryer.
The purpose of a drum dryer is to heat and dry the
aggregates of the mix. Aggregates temperature controls the
temperature of the mix. If the aggregates has been heated
excessively, the asphalt will harden during mixing. If the
aggregates have not been heated adequately, it is difficult to
coat them completely with asphalt.

8. every percent increase in aggregate moisture will increase
dryer fuel consumption 10% the aggregates from the hot
screen are stored in the hot bins. Aggregates from the hot bins
is dropped into a weight hopper situated below the bins and
above the pug mill. To control the weighting of the blended
aggregates, the weight hopper is charged one hot bin at a time.
After charging the weight hopper gates are open to discharge
the aggregates into the pug mill.
The asphalt is pumped to the weight tank ready for
discharging into the pug mill. Aggregates and asphalt are
thoroughly mixed in the pug mill. The mixing process
generally takes about 1 min 15 sec for loading with the dry
materials and 45 sec for mixing with the asphalt cement.

9. the capacity of the plant is a function of the pug mill size
and the mixing time. Typical batch quantities range from 1.5
to 5 tons. A batch plant with a ton pug mill can produce 300
tone of mix per hour. The mixing temperature ranges from
225 to 350˚ F, measured immediately after discharge from
the pug mill.

10. 2. Asphalt paver

11. An asphalt paver consist of a tractor, either track
or rubber tired, and a screed. The tractor power unit has a
receiving hopper in the front and a system of salt conveyors to
move the mix through a tunnel under the power plant to the
rear of the tractor unit. At the rear of the tractor unit, the mix is
deposited on the surface to be paved. Angers are used to spread
the asphalt evenly across the front of the trailing screed. The
creed controls the asphalt placement width and thickness, and
imparts the initial finish and compaction to the hot mix
material.

12. Advantages of paver:
1. Uniform thickness of asphalt concrete in obtained.
2. The thickness of the asphalt concrete can be changed.
3. Suitable straight camber can be provided.
4. Width of pavement can be increase and decrease.
5. Speed of work is faster.
6. Repair and maintenance cost of the surface can be
decrease.

13. 1. Smooth wheel rollers
2. Pneumatic rollers
3. Sheep foot rollers
Roller

14. There are three types of smooth wheel rollers
smooth wheel rollers
Conventional roller
Tendem roller
Three axel tendem roller

15. Conventional roller
Weight 2 ton to 15 ton

16. Tendem roller
Weight 1 tone to 14 tone

17. Weight 12 tone to 18 tone
Three axel tendem roller

18. Sheep foot rollers

19. The sheep foot rollers consists of a hollow drum
with a large number of small projections on its surface these
projections penetrate the soil layer during the rolling
operations and cause compaction. The drum can be filled
with water or ballast to increase the mass.
The loaded weight per drum ranges from 1.5 to 10
ton, and the foot pressure range from 8 to 35 kg/cm².
The sheep foot rollers are ideally suited for
compaction of cohesive soils. The rollers compact the soil
by the combination of tampering and kneading action.

20. Pneumatic tyred rollers

21. Pneumatic tyred rollers used compressed air to
develop the required inflation pressure. The roller generally
consist 9 to 11 wheels fixed on two axes with the pneumatic
tyres so spaced that a complete coverage is obtained with each
pass of the roller. The gross mass of the rollers various from 5
to 200 ton.
the roller compacts the soil primarily by kneading
action this rollers are effective for compaction in cohesive as
well as cohesion less soils.
light rollers(up to 20 ton) are effective for compacting
soil layer of small thickness up to 15cm, where as heavy rollers
are useful for layers of thickness up to 30cm.