Unit-1 Chapter 3 Hill Roads

2. INTRODUCTION
• A hill road may be defined as the one which passes
through a terrain with a cross slope of 25% or more.
• The roads constructed in mountainous regions of a
country are known as hill roads or ghat roads.
• These roads present great difficulty in their
alignment, design, construction and maintenance.
• Hence, a strong stable and feasible road must be
present in hilly areas for overall development of
other sectors as well.

3. IMPORTANCE OF HILL ROADS
• Economic Development
• Industrial Development
• Forest Wealth
• Strategic Considerations
• Tourism

4. IMPORTANCE OF HILL ROADS
Economic Development:
• Hilly regions are backwards as far as modern
civilization, culture and education is concerned. The
main activity of people in these area is agriculture.
• The lands of these areas are mainly suitable for
variety of fruits and vegetables like apple, strawberry,
cherry, apricots, snow peas, lettuce etc.
• The economic life of these people can be improved if
these fruits and vegetables are transported outside.

5. IMPORTANCE OF HILL ROADS
Industrial Development:
• There are certain areas on hills where limestone has found
abundantly which is useful raw material for cement industry.
• In the hills of Himachal Pradesh, Limestone is found in
abundance in Bilaspur, Sirmour, Mandi and Solan District.
• In Recent survey, the Uranium deposit has also been found in
Kullu and Hamirpur district.
• So the industrial development can also help in boosting up
the economic growth of the country and thus need of roads
for making a connectivity for various purposes is required.

6. IMPORTANCE OF HILL ROADS
Forest Wealth:
• Most of the hilly regions contains huge forest wealth.
• Forest plays an important role in economic
development for the country.
• Several goods such as Timber, Teak, Sal etc. which in
terms serves as raw material for many industries.
• Therefore an efficient transport system is important
for carrying these valuable goods to the places where
it needed.

7. IMPORTANCE OF HILL ROADS
Strategic Consideration
• Transport system can help in strategic development of
backward areas.
• Many villages, towns of backward area affects due to lack
of transportation system.
• Thus to build a bridge between communities of backward
areas with healthcare centres, school or Institutional
building can promote the health and lifestyle of people.
• In case of emergency such as war, a good transport
system also can help for military purpose for moving
army from one place to another.

8. IMPORTANCE OF HILL ROADS
Tourism:
• Some of the hilly areas present a scenic beauty which
attracts thousands of local and foreign tourists.
• The construction of hill roads is the main controlling
factor for the development of tourism.

9. CLASSIFICATION OF HILL ROADS
• According to general classification:
National Highway (NH)
• State Highway (SH)
• Major District Road (MDR)
• Other District Road (ODR)
• Village Road (VR)

10. CLASSIFICATION OF HILL ROADS
Classification according to Border Road
Organisation (BRO):
• National Highways
• Class 9 (6m wide for 3 tonnes vehicles)
• Class 5 (4.5 m wide for 1 tonnes vehicles)
• Class 3 (2.45 m to 3.65 m wide for Jeeps)

11. CLASSIFICATION OF HILL ROADS
Classification according to use:
• Motor Roads
• Bridle Paths
• Village Tracks

12. CLASSIFICATION OF HILL ROADS
Motor Roads:
• In the hilly regions, motor roads are the main
communication system.
• These roads are suitable for all types of traffic.
Hence, this road can be used by all sorts of traffic.
• These roads can have one or more lane width.

13. CLASSIFICATION OF HILL ROADS
Bridle Paths:
• These are the main roads for pedestrian traffic.
• Bridle Paths are used by pedestrians and Mule traffic.
Bridle paths serve as feeder roads to motor roads.
• Width of these roads generally kept as 2-3 m and
side slope of 1 in 8 to 1 in 10 is provided.
• If these roads are used by Jeeps, then width is taken
as 2.45 to 3.65 m.

14. CLASSIFICATION OF HILL ROADS
Village Paths:
Village paths act as a connector between villages and
other important areas in hilly regions.
These are usually 1m to 1.2 m wide and may have a
slope of more than 45 degrees.
For these types of paths, the recommended value of
the ruling gradient is 1 in 7.5 and the limiting
gradient is 1 in 5

15. TYPES OF CURVES ON HILLY ROADS
• Hair Pin Bend Curves
• Salient Curves
• Re-entrant curves

16. TYPES OF CURVES ON HILLY ROADS
Hair Pin Bends:
• Hair pin bend is a bend in a road with a very acute
inner angle, making it necessary for an oncoming
vehicle to turn about 180° to continue on the road.
• It is named for its resemblance to a bent
metal hairpin.
• It is located on the hill side having minimum slope
and must be same from view point of landslide and
ground water.

18. TYPES OF CURVES ON HILLY ROADS
Salient Curves:
• Those curves having the convexity at the outer edge of a hill
road, called as salient curves.
• The centre of the curvature of the salient curves lies towards
hillside.
• Such curves are very dangerous for fast moving traffic so
speed limit is restricted.
• This type of curve occur on the road length constructed on
the ridge of the hill.
• The bend so formed at the salient curve in a hill road is known
as corner bend.

19. TYPES OF CURVES ON HILLY ROADS
• At such a curve or corner bends, the portion of the projecting
hill side is usually cut down to improve the visibility.
• Therefore the outer edge of the curve is essentially provided
with parapet wall for the protection of vehicles from falling
down of the hill slope.

20. TYPES OF CURVES ON HILLY ROADS
Re-entrant Curve:
• Those curves having their convexity on the inner edge of a hill road
are called as re-entrant curves.
• This type of curve occur in the road length constructed in the valley
of a hill.
• These curves are less dangerous as they have provided adequate
visibility to the fast moving vehicles.
• At such curves, the parapet walls are only provided for the safety of
fast moving traffic.