5. Introduction
A line of communication (travelled way) using a
stabilized base open to public traffic, primarily for the
use
of
road
motor
vehicles
including
"bridges,
tunnels,
supporting
structures
junctions, crossings and toll roads.
A 1984 ruling said "the land over which a public right of
way exists is known as a highway.
Ways that allow the movement of motor-vehicles, and
the term rights of ways can be used to cover the wider
usage.
6. Classification Of Roads
National Highways
Important roads &connect state capitals, ports and
foreign highways. They also include roads of military
importance. They are financed by the central
government.
State Highways
Connect important cities and district head quarters
in the state, national highways & state highways of
neighbouring states. Financed by state government
roads and buildings department.
7. District Roads
These are the roads within a district.
i) Major District Roads
ii) Minor District Roads
Village Roads
They connect villages with each other and to the
nearest district road.
8. Road Structure
Road Structure Depends Upon the key What is it for!
There are two main types of pavement (road structure)
i) Flexible Roads
ii) Rigid Roads
Flexible Carriageway Construction
When a road is built, the surface is dug-out down to the
designed depth of the intended road. The sub-grade is the
ground below the road layers which is exposed once the
ground has been dug out ready to build the road.
10. Rigid Road Construction:
Rigid pavement is the technical term for any road
surface made of concrete.
The largest advantages to using concrete pavement are
in its durability and ability to hold a shape.
A surface layer, made up of slabs of Portland cement
concrete (PCC), sits on top of a handful of sub-layers.
The layer directly under the PCC is more flexible than
the concrete, but still quite rigid.
11. Materials Used In Road Construction
1.Asphalt
Asphalt also known as bitumen is a sticky, black and
highly viscous liquid or semi-solid form of petroleum.
Asphalt is used in road construction, where it is used
as the glue or binder mixed with aggregate particles to
create asphalt concrete.
It is use to prepare asphalt emulsion, Hot mix asphalt
concrete, cold mix asphalt concrete.
12. Aggregates
1.Granite aggregates are crushed hard rock of granular
structure, being the most common on Earth.
Fractions of Aggregates
0-5mm the smallest granite aggregates fractions are
used, besides the road construction, for decoration
and paving paths, for covering sports grounds.
5-10mm fraction, is used for road construction and
production of concrete.
10-40mm a road sub base also used for road
maintenance operations.
13. 2.Gravel aggregates are aggregates acquired as the
result of sifting quarried rock and by crushing natural
stone rock.
3. Limestone aggregates are a product of the
crushing of sedimentary rock - limestone, which is
composed mainly of calcite (calcium carbonate ).
4.Slag Aggregates are obtained by crushing of smelter
slag or by special treatment of fire-liquid slag melt
(molten slag aggregates).
14. Machinery used in Road Construction
Machinery used in road constructions are used for
rough grading, fine grading, surfacing, paving,
compaction and to control moisture level.
AIR-TRACK DRILL
A drilling machine for quarry or opencast blasting
equipped with tracks and operated by
independent air motors.
16. CHIP SPREADER
A chip spreader lays down the aggregate on top of a
bituminous binder which is then rolled by a
compactor.
17. COLD PLANERS
A cold planer (also known as a pavement planer,
pavement recycler, mill or asphalt milling machine) is
a machine used to remove bituminous pavement or
asphalt concrete from roadways.
19. Vibratory Steel Drum compactor
Vibratory roller compactor is used to compact soil, gravel,
concrete, or asphalt in the construction of roads and
foundations.
20. Pneumatic tired roller
Pneumatic tire compactors are used on small to
medium size compaction jobs,
bladed, granular base materials.
primarily
on
21. Padded Drum Compactor
Padded drum compactors are usually applied to
compact soil, gravel, concrete, or asphalt in the
construction of roads and foundations.
22. OIL DISTRIBUTORS
Asphalt distributors are used to apply prime or tack
coats on a surface in preparation for paving.
23. PAVER
A paver is a machine used to lay asphalt on roadways.
It is normally fed by a dump truck which brings hot
asphalt.
24. Maintenance and Rehabilitation
Roads are exposed to tremendous loads that will
sooner or later leave their marks on them. A time will
come when every road will be in need of a general
overhaul. Following methods are used.
Replacing the Pavement
By removing only those layers of a road structure that
are actually damaged.
Additional conditions frequently stipulate that the
flow of traffic must be maintained in spite of extensive
reconstruction measures.
26. Paving thin Layer Hot
Paving thin layers in hot application is a viable option
for rehabilitating of Limited damaged roads.
At first surface deformations are removed by cold
milling machines fitted with fine milling drums to
create an even, slightly roughened road surface.
When using a paver with integrated spray module, the
paver seals the base by spraying a tack coat of polymermodified bitumen emulsion with a minimum bitumen
content of 60% .
27.
28. Paving thin layers Cold
Fast and economically efficient alternative to replacing
the entire road pavement.
Traffic safety is hazarded when the road surface gets
slippery, when wheel ruts have dug into the
pavement, or when the road is covered with bumps
and deformations.
Cold milling machines fitted with fine milling drums
prepare the road surface for application of the
thin, cold pavement layer.
29. It works at a maximum milling depth of 50
mm, reprofiling the pavement by means of modern
levelling technology to produce a level surface. The
slightly roughened surface texture produced by fine
milling offers.
