Hill road definition, Design Issue of Hill Road, Special Consideration Hill road, Route Selection, Alignment- Hill Road, Engineering Data-Hill Road, Geometric Design- Hill Road, Hair Pin Bends, Hill Road Capacity, Set back Distance, IRC Codes- Hill Road design, IRC Code- Hill road Drainage, Hill road-Protective Works, Hill road- Drainage, Hill road- Maintenance, Hill road- Standard References

1. Prof. Samirsinh P Parmar
Department of Civil Engineering
Faculty of Technology
Dharmasinh Desai University
Nadiad-387001
E-mail: samirddu@gmail.com, spp.cl@ddu.ac.in
B.Tech Civil Engineering – Semester-VII
Highway Engineering

2. Contents
• Hill Road Definition
• Design Issues in Hill Roads
• Special Consideration in Hill Road Design
• Route Selection
• Engineering Data for Design
• Geometric Design Standards
• Design of Hair-pin Bends
• Climbing Lane
• Other Geometric Design Aspects
• Case Study of NH-21 (Kiratpur Nerchowk Alignment)
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3. Hill Road Definition
• Hill road is defined as the one which passes through a terrain with a cross slope of 25% or more.
• IRC:SP:73-2015 and IRC:SP:84-2014 have merged the Mountainous and Steep Terrain having
Cross Slope more than 25%.
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4. Design Issues in Hill Roads
• Design and Construction of Hill roads are more complex than in plain terrain due to
factors summarized below:
 Highly broken relief with vastly differing elevations and steep slopes, deep gorges etc. which
increases road length.
 The geological condition varies from place to place.
 Variation in hydro-geological conditions.
 Variation in the climatic condition such as the change in temperature due to altitude difference,
pressure variation, precipitation increases at greater height etc.
 High-speed runoff due to the presence of steep cross slopes.
 Filling may overload the weak soil underneath which may trigger new slides.
 Need of design of hairpin bends to attain heights.
 Need to save Commercial and Residential establishments close to the road.
 Need to save the ecology of the hills.
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5. Special Consideration in Hill Road Design
• Alignment of Hill Roads
 The designer should attempt to choose a short, easy, economical and safe comforting route.
• General considerations
 When designing hill roads the route is located along valleys, hill sides and if required over
mountain passes.
 Due to complex topography, the length of the route is more.
 In locating the alignment special consideration should be made in respect to the variations in:
 Temperature
 Rainfall
 Atmospheric pressure and winds
 Geological conditions
 Resettlement and Rehabilitation considerations
 Environment Considerations
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6. Special Consideration in Hill Road Design
• Temperature
 Air temperature in the hills is lower than in the valley. The temperature drop being approximately 0.5° per
100 m of rising.
 On slopes facing south and southwest snow disappears rapidly and rain water evaporates quickly while on
slopes facing north and northeast rain water or snow may remain for the longer time.
 Unequal warming of slopes, sharp temperature variations and erosion by water are the causes of slope
failure facing south and southwest.
• Rainfall
 Rainfall generally increases with increase in height from sea level.
 The maximum rainfall is in the zone of intensive cloud formation at 1500-2500 m above sea level. Generally,
the increase of rainfall for every 100 m of elevation averages 40 to 60 mm.
 In summer very heavy storms/cloud burst may occur in the hills and about 15 to 25% of the annual rainfall
may occur in a single rainfall. The effects of these types of rainfall are serious and should be considered in
design.
• Atmospheric pressure and winds
 Atmospheric pressure decreases with increase in elevation.
 At high altitudes, the wind velocities may reach up to 25-30 m/s and depth of frost penetration is also 1.5 to
2 m.
 Intensive weathering of rocks because of sharp temperature variations.
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7. Special Consideration in Hill Road Design
• Geological conditions
 The inclination of folds may vary from horizontal to vertical stratification of rock. These folds
often have faults. Limestone or sandstone folds may be interleaved with layers of clay which
when wetted may cause fracturing along their surface. This may result in shear or slip fold.
 The degree of stability of hill slopes depends on types of rock, degree of strata inclination or dip,
occurrence of clay seams, the hardness of the rocks and presence of ground water.
 When locating the route an engineer must study the details of geological conditions of that area
and follow stable hill slopes where no ground water, landslides, and unstable folds occur.
• Resettlement and Rehabilitation
 Due to limited availability of flat areas and connectivity issues, most of the residential and
commercial activity happens very close to the road leading to large scale R&R and becomes a
challenge in alignment design.
• Environment
 Hills are ecologically sensitive areas relatively untouched by human activity. The alignment
design must attempt to minimize tree cutting and large scale earth filling/cutting to minimize
damage.
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8. Route Selection
• Hill road alignment may follow alignment at Valley bottom or on a ridge depending on the
feasibility of the road. The first is called River route and the second is called Ridge route.
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 River route
 Most frequent case of hill alignment as there is a great
advantage of running a road at a gentle gradient.
 Runs through lesser horizontal curvature.
 Requirements for the construction of bridges over
tributaries.
 Construction of special retaining structures and
protection walls on hill side for safe guarding the road
against avalanches in high altitude areas.
 Benefit of low construction cost and operation cost.
 Ridge route
 Characterized by the very steep gradient.
 Large number of sharp curves occurs on the road with
hair pin bends.
 Extensive earthwork is required.
 The requirement for the construction of special
structures.
 High construction and operation cost.
Road along River Route
Road along Ridge Route

9. Engineering Data for Design
• The design data includes:
 The terrain classification all along the alignment - to be established through topographic data/ Contours of the area
using Satellite Imagery.
 All features like river course, streams, cross-drainage structures (for existing alignment), flooding areas, high
flood levels, landslide areas, snow/avalanche prone areas etc.
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 River Morphology and Regime data.
 Chainage wise inventory of the side slope material
type i.e. soil with classification and properties,
rock type and its structural geology of the area.
 Hydrological data for all stream and river
crossings.
 Available material and resources that can be used
in the road construction.
 Geometric standards.
Contour Data for Design

10. Geometric Design Standards
• The various Design Standards being followed in the India for the design of Hill
Road are:
 IRC:SP:48-1998- Hill Road Manual.
 IRC:52-2001 - Recommendations About the Alignment Survey and Geometric Design of Hill Roads.
 IRC:SP:91-2010- Guidelines for Road Tunnels.
 IRC:SP:73-2015- Manual of Specifications and Standards for Two Laning of Highways with Paved
Shoulder.
 IRC:SP:84-2014- Manual of Specifications and Standards -for Four Laning of Highways through-
Public Private Partnership.
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11. Geometric Design Standards
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• Hill Road Capacity
Type of Road
Design Service Volume in PCU per day
As per IRC:SP:48-1998 and
IRC:52- 2001
As per IRC:SP:73-2015 &
IRC:SP:84-2014
For Low Curvature
(0-200 degrees per
km)
For High Curvature
(above 0-200 degrees
per km)
Level of
Service ‘B’
Level of
Service ‘C’
Single lane 1,600 1,400 - -
Intermediate
lane
5,200 4,500 - -
Two Lane 7,000 5,000 9,000 -
Four Lane - - 20,000 30,000

12. Geometric Design Standards
• Design Speed:
 The design speed for various categories of hill roads are given below:
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Road
Classification
As per IRC:SP:48-1998 and IRC:52- 2001
As per IRC:SP:73-2015
& IRC:SP:84-2014
Mountainous Terrain Steep Terrain
Mountainous and Steep
Terrain
Ruling Minimum Ruling Minimum Ruling Minimum
National and
State Highways
50 40 40 30 60 40
Major District
Roads
40 30 30 20 - -
Other District
Roads
30 25 25 20 - -
Village Roads 25 20 25 20 - -

13. Geometric Design Standards
• Sight Distance:
 Visibility is an important requirement for safety on roads.
 It is necessary that sight distance of sufficient length is available to permit drivers
enough time and distance to stop their vehicles to avoid accidents.
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Design
Speed
(Km/h)
As per IRC:SP:48-1998 and IRC:52-
2001
As per IRC:SP:73-2015 & IRC:SP:84-2014
Mountainous and Steep Terrain
Stopping Sight
Distance (m)
Intermediate
Sight Distance
(m)
Safe Stopping
Sight Distance (m)
Desirable Minimum
Sight Distance (m)
20 20 40 - -
25 25 50 - -
30 30 60 - -
35 40 80 - -
40 45 90 45 90
50 60 120 60 120
60 - - 90 180

14. Geometric Design Standards
• Minimum Radius of Horizontal curves
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Classification
As per IRC:SP:48-1998 and IRC:52- 2001
As per IRC:SP:73-
2015 & IRC:SP:84-
2014
Mountainous terrain Steep terrain
Mountainous and
Steep
Area not affected by
snow
Snow Bound Areas
Area not affected by
snow
Snow Bound Areas
Ruling
Minimum
Absolute
Minimum
Ruling
Minimum
Absolute
Minimum
Ruling
Minimum
Absolute
Minimum
Ruling
Minimum
Absolute
Minimum
Desirable
Minimum
Radius
Absolute
Minimum
Radius
National Highway
and State
Highways
80 50 90 60 50 30 60 33 150 75
Major District
Roads
50 30 60 33 30 14 33 15 - -
Other District
Roads
30 20 33 23 20 14 23 15 - -
Village Roads 20 14 23 15 20 14 23 15 - -

15. Geometric Design Standards
• Typical Cross-sections – 2 lane carriageway
(as per IRC:SP:73-2015)
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Road Classification Carriageway Width (m) Shoulder Width (m)
National and State Highways
i) Single lane 3.75 2 x 1.25
ii) Double Lane 7.00 2 x 0.9
Major District Roads and Other District Roads 3.75 2 x 0.5
Village Roads 3.00 2 x 0.5
 As per IRC:SP:48-1998 and IRC:52- 2001

16. Geometric Design Standards
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 Typical Cross-sections – 4 Lane Carriageway Widening Towards Valley Side (as per
IRC:SP:84-2014)

17. Geometric Design Standards
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 Typical Cross-sections – 4 Lane Carriageway Widening Towards Hill Side (as per
IRC:SP:84-2014)

18. Geometric Design Standards
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 Typical Cross-sections – 4 Lane Carriageway Widening on Both Side (as per
IRC:SP:84-2014)

19. Geometric Design Standards
• Reverse curves are needed in difficult terrain.
• It should be ensured that there is sufficient length between the two curves for
introduction of requisite transition curves.
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20. Geometric Design Standards
• Curves in same direction separated by short tangents, known as broken – back curves.
• Should be avoided, as far as possible, in the interest of aesthetics and safety and replaced
by a single curve.
• If this is not feasible, a tangent length corresponding to 10 seconds travel time must at
least be ensured between the two curves.
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21. Geometric Design Standards
• Compound curves may be used in difficult topography but only when it is impossible to fit
in a single circular curve.
• To ensure safe and smooth transition from one curve to the other, the radius of the flatter
curve should not be disproportional to the radius of the sharper curve.
• A ratio of 1.5:1 should be considered the limiting value.
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22. Geometric Design Standards
• Set Back Distance
 Requisite sight distance should be available to sight the inside of horizontal curves.
 Lack of visibility in the lateral direction may arise due to obstruction like walls cut, slopes, wooded
areas, high crops etc.
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23. Geometric Design Standards
• Vision Berm
 Where there is a cut slope on the inside of the
horizontal curve, the average height of sight
line can be used as an approximation for
deciding the extent of clearance.
 Cut slope shall be kept lower than this height
at the line demarcating the set back distance
envelop, either by cutting back the slope or
benching suitably, which is also generally
known as vision berm.
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24. Geometric Design Standards
• Vertical Alignment
 The vertical alignment of a hill road need to be adaptive by:
 Adopting mild vertical grades for reduced potential for erosion of road bed.
 Designing vertical profile compatible with natural topography for optimum and balanced cut-fill
quantities hence generate less spoil.
 Keeping finished road level and fill slopes higher than the high flood level (HFL).
 Avoiding interception with water table line which cause wet pavement layers.
 Optimizing the cut height at landslide and rock fall prone areas.
 Ensure Easy Access to Properties.
 Ensure Safer Junction Design.
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25. Geometric Design Standards
• Vertical Alignment
 Vertical curves are introduced for smooth transition at grade change.
 Both Summit curves and Valley curves should be designed as Square parabola.
 The Length of vertical curves is controlled by sight distance requirements.
 Curves with greater length are aesthetically better.
 Recommended gradients for different terrain conditions, except at hair pin bends, are given below:
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As per IRC:SP:48-1998 and IRC:52- 2001
As per IRC:SP:73 &
IRC:SP:84
Classification of
Gradient
Mountainous Terrain and
Steep Terrain more than
3000 m above MSL
Steep Terrain up
to 3000 m above
MSL
Mountainous Steep
Ruling Gradient 5% 6% 5% 6%
Limiting Gradient 6% 7% 6% 7%
Exceptional 7% 8% - -

26. Design of Hair-pin Bends
• At unavoidable circumstances Hair-pin Bends may be designed as Circular
Curve with Transitions or as Compound Circular curves.
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Design Criteria for Hair-pin Bends As per IRC:SP:48-1998 and IRC:52- 2001
Description Criteria
Min Design Speed 20 Km/h
Min Roadway width at apex
NH/SH
11.5m (Double lane)
9.0m (Single lane)
MDR/ODR 7.5m
Village Roads 6.5m
Min radius for the inner curve 14 m
Min Length of transition Curve 15 m
Gradient
Maximum 1 in 40 (2.5%)
Minimum 1 in 200 (0.5%)
Max Super elevation 1 in 10 (10%)
Minimum Intervening distance between the successive hair pin
bends
60m

27. Illustrations of Hair-pin Bends
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28. Climbing Lane
• Climbing Lane shall be provided in order to address the necessity of making
available separate lane for safe overtaking for vehicle travelling uphill.
• IRC:52-2001, IRC:SP:73-2015 and IRC:SP:84-2014 mandates for provision of
Climbing lanes but no warrants are provided.
• AASHTO provides the guidelines for the provision of Climbing lanes:
 Up Grade traffic flow rate in excess of 200 vehicles per hour.
 Up Grade truck flow rate in excess of 20 vehicles per hour.
 One of the following conditions exists:
 A 15 km/h [10 mph] or greater speed reduction is expected for a typical heavy truck.
 Level of Service ‘E’ or ‘F’ exists on the grade.
 A reduction of two or more levels of service is experienced when moving from the approach segment to
grade.
 In addition, safety considerations may justify the addition of a climbing lane regardless of
grade or traffic volumes.
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29. Other Geometric Design Aspects
• Escape Lane
• Grade Compensation at Curves
• Passing Places
• Vertical and lateral Clearances
• Widening at Curves
• Co-ordination of Horizontal and Vertical Alignments
• Tunnels
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Escape lane
Passing Places Widening at Curves

30. Typical Section for Tunnels
• Typical Cross section for 3-lane Tunnel as per IRC SP 91-2010
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31. Design
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PROTECTIVE WORKS FOR HILL
ROADS

32. Design
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In order to give stability and a sense of safety to the hill roads, the following three
types of protective works are provided:
(1) Retaining walls
(2) Breast walls
(3) Parapet walls.

33. 1. Retaining walls:
• The formation of a hill road is generally prepared by the excavation of the hill and the
material which is excavated is dumped or stacked along the cut portion.
• The retaining wall is constructed on the valley side of the roadway to prevent the sliding
of backfilling as shown in figure.
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Thus the main function of a retaining wall
for hill roads is to retain the back filling and
it is provided at the following places:
1. at all re-entrant curves;
2. at places where the hill section is partly
in cutting and partly in embankment; and
3. at places where the road crosses drainage.
Figure. Retaining wall and breast wall for
protective works for hill road

34. 1. Retaining walls:
• Where stones are economically and easily available, it is customary to construct the
retaining walls in dry stone masonry as it permits easy drainage of seeping water.
• The design of retaining walls is based on rules-of-thumb and the performances of
similar existing retaining walls.
• The minimum width of 600 mm is kept at the top.
• The rear side is kept vertical.
• The front side is provided with a batter of 1 in 4.
• If the height of the retaining wall exceeds 6 m or so, the bands of coursed rubble
masonry in cement mortar at vertical and horizontal intervals of about 3 m are
constructed to grant additional stability to the wall.
• To facilitate the drainage of the water behind the retaining wall, suitable weep holes
at vertical height of 1 m and horizontal spacing of 1.2 m are provided with slope
outwards.
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35. 2. Breast walls:
• The cut portion of hill is to be prevented from sliding and the wall which is
constructed for this purpose is known as breast wall. See figure.
• The breast walls are provided with a front batter of 1 in 2 and a back batter
of 1 in 3.
• The back batter may be provided either in one straight batter or in the form
of projections.
• If the height of the wall is less than 2 m, the entire section is made in
random rubble stone masonry.
• If the height of wall exceeds 2 m, the top portion of 2 m height alone is made
in random rubble masonry and the remaining portion is constructed in
cement mortar of proportion (1:6).
• The weep holes, as in case of retaining walls, are provided with slope
outwards and sometimes, the vertical gutters connecting the weep holes to
the side drain are provided.
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36. 3. Parapet walls:
• The parapet walls are usually provided all along the valley side of the road
except where the hill slope is very gentle.
• They are constructed immediately above the retaining wall, as shown in
figure. and they prevent the wheels of the vehicles from coming on the
retaining wall.
• It is to be noted that the construction of a parapet wall merely gives a sense
of security to the driver and the passengers and it is very rare unless
constructed in stone masonry with cement mortar that they act as protecting
structures in the event of an accident.
• The parapet walls are usually of wall type with uniform thickness of 600 mm
and height of 600 mm above the berm level.
• They can also be constructed of R.C.C. posts of 150 mm x 150 mm section
with 1 m height above ground level and 450 mm below ground level and
spaced at 1 m center to center.
• In case of hard rocky stratum, the parapet walls may be replaced by the
railing of cast-iron.
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37. Design
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DRAINAGE IN HILL ROADS
Sub-surface
drainage:
Surface
drainage:
DRAINAGE IN
HILL ROADS

38. 1. Subsurface Drainage
• The seepage flow of water on hills creates problems during and after monsoons.
• The level of seepage water may be at, above, or below the road level depending upon
several factors such as depth of hard stratum and its inclination, the quantity of
underground flow of water, etc.
• The seepage flow also causes the weakening of the roadbed and the pavement and it
also causes problems of slope stability.
• It is, therefore, necessary to control the seepage flow by adopting the suitable
method of the sub-surface drainage system.
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39. 2. Surface drainage:
• For carrying the surface water, the side drains are provided only on the hill side
of the road, as shown in figure.
• There is limitation in the formation width of road and hence, these drains are
constructed of such a shape that the vehicles could utilize the space of side drains
in case of an emergency for crossing or parking.
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Fig.6. Angle side
drain for hill road
drainage works
Fig.7. Kerb and
channel side drain
Fig.8. saucer side
drain

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In order to prevent the side drains from overloading and thereby
causing the road surface flooding, the following two measures
should be taken:
1. Provision of catch water drain or intercepting ditch above the
side drain; and
2. Suitable cross-drainage work to divert the water through the
road on downside of the hill.

41. Design
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MAINTENANCE OF HILL
ROADS

42. MAINTENANCE OF HILL ROADS
• The hill roads because of their peculiar location require careful attention
in their maintenance.
• For the purpose of convenience, the maintenance problems of the hill
roads can be grouped into the following four categories:
• (1) Control of avalanches
• (2) Drainage structures
• (3) Prevention of land slides
• (4) Snow clearance.
• Each of the above category will now be briefly described.
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43. Control of avalanches:
• An avalanche indicates a large mass of loosened snow, earth, rocks, etc.
which suddenly and swiftly slides down a hill.
• Where there are chances for an avalanche to occur, suitable remedial
measures may be adopted so that minimum damage occurs to the road
structures.
• One of such preventive measure which is commonly adopted is the
construction of galleries above the road which permit the avalanche to slide
over the gallery roof without inducing impact loads.
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
43

44. Drainage structures:
• The drainage structures such as catch water drains, catch pits, side drains
and culverts are to be periodically inspected and cleaned off all the debris
and blockages which prevent the smooth flowing of water in such structures
during rains.
• As a precautionary measure, the upper slopes are planted with trees to
reduce considerably scouring action of unstable ground due to rains.
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
44

45. Prevention of land slides:
• The term land slide is used to indicate the downward and outward
movement of slope-forming materials composed of natural rock soils,
artificial fills or combinations thereof.
• The landslides move along the surface of separation by falling, sliding and
flowing.
• When the shear stresses exceed the shear strength of the soil, the movement
in the form of land slide occurs.
• Hence, anything which contributes towards a decrease in shear strength of
the soil or an increase in the shear stress can cause a land slide.
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
45

46. The decrease in shear strength of the soil takes place
mainly due to the following causes:
a) decrease in inter-granular pressure;
b) formation of faults in bedding planes of strata:
c) hair-cracking due to alternate swelling and shrinkage of the soil
structure;
d) increase in water content and consequent swelling and increase in pore
water pressure;
e) seepage pressure of percolating ground water; etc.
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
46

47. The increase in the shear stress takes place mainly due to
the following causes:
i. External loads due to traffic:
ii. Increase in water or moisture content;
iii. Increase in weight due to accumulation of snow:
iv. Removal of part of mass of excavation or removal of retaining wall or
increase in slope angle:
v. Shocks and vibrations due to earthquakes or blasting;
vi. Undermining due to excavation or erosion; etc.
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
47

48. For prevention and correction of land slides, the commonly
adopted techniques are as follows:
i. Construction of buttress at toe and providing suitable retaining
structures;
ii. Effective drainage measures to intercept and divert water:
iii. Relocation or changing the position of the highway:
iv. Slope treatment to minimize the erosion and to improve the stability
conditions; etc.
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
48

49. Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
49
CASE STUDY OF NH-21
(Kiratpur Nerchowk Alignment)

50. Index Map
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
50
Start of Project
Road
End of Project
Road
Length of Existing Alignment = 116.8 Km

51. Major Bottlenecks along the Existing Road
• Heavy Settlements along the
Project Road.
• Settlements along Hill Side.
• Deep Gorge Section.
• Barmana Cement Factory.
• Steep Hill and River Satluj
Running Parallel to the Existing
Road between Km.154+000 to
Km.156+000.
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
51

52. Major Bottlenecks along the Existing Road
• Bridge across River Satluj at Km
157+000
• Sharp hair pin bends
• Steep grade section
• Sundar Nagar lake
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
52

53. Capacity Augmentation – Base Year Traffic
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
53
Station
No.
Chainage
(km)
Location of
Survey
ADT
Peak Hour
Flows
Peak
Hour
proportion
in
daily
Vehicle
Vol.
Peak
Hour
proportion
in
daily
PCU
Vol.
Veh’s PCUs Veh’s PCUs
MCC-1 138+500 Bamta Village 5439 9841 324 547 5.96 5.56
MCC-2 167+000 Zedol Village 6526 9914 412 542 6.31 5.47

54. Key Plan
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
54
Tunnel Length (Km)
T1 1.75
T2 0.65
T3 0.4
T4 1.41
T5 0.86
Total 5.07
Length of Existing Alignment = 116.80 Km,
Length of Revised Alignment = 84.38 Km,
Saving in Length = 32.42 Km
T5
T4
T3
T2
T1

55. Salient Features of the Project
Capacity Augmentation/
Development Scope
4 Laning
Major Bridges
15 nos., Longest Bridge of 650m over Govind
Sagar lake
Proposed Bypasses
2 (Sunder nagar Bypass – 5.678 Km, Ner Chowk
Bypass – 4.551 Km)
Major Realignments
New alignment along Govind Sagar Lake/Satluj
Beas River – 32.570 Km
Tunnels 5 nos. for Total length of 5.07 Km
Toll Plazas 2 nos.
Total Civil Cost INR 1818.47 Cr. (Rs. 21.64 Cr/km)
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
55

56. References:
• https://www.engineeringenotes.com/highway-construction/hill-roads-
alignment-geometric-design-and-maintenance-of-hill-roads/48805
• https://abhashacharya.com.np/wp-content/uploads/2017/04/Hill-Roads.pdf
Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
56

57. Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
57
Reference:
https://law.resource.org/pub/in/bi
s/irc/irc.gov.in.052.2019.pdf
Reference:
https://mis.wbprd.gov.in/Engin
eering/Codes/IRCSP48.pdf

58. Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
58
Reference:
https://pwd.mizoram.gov.in/uploads/attachments/08b1c6d
7df31a927ed3b616d49b42e31/irc-sp-0422014-guidelines-
for-road-drainage.pdf
For Field
Application
Refer Standard
References of
IRC

59. Design
of
Hill
Roads,
Highway
Engg.
Sem-VI,
SPP_CL,
DoCL,
DDU,
Nadiad
Thank you