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STUDY OF ROAD
ACCIDENTS IN INDIA
INTRODUCTION
 Road accidents are one of the causes of disability, injury
and death.
 India has the highest road traffic accident rate worldwide
with over 140000 deaths annually, beating even China.
Every hour nearly 14 lives are lost due to road accidents.
 Most accidents occur during peak hours considered an
‘unsafe’ or dangerous time due to complex flow pattern of
vehicular traffic.
 Thus traffic engineers have to undertake a big
responsibility of providing safe traffic movements to the
road users and ensure their safety.
 Road accidents cannot be totally prevented but by suitable
traffic engineering and management the accident rate can
Studies on road accidents in India
COMMON CAUSES OF ROAD ACCIDENTS
 SPEEDING
 CARELESS
DRIVING
 DRINKING
 SEAT
DRIVING
BELT WEARING
 INEXPERIENCE
 LOSS
OF CONTROL
 FAILED
 AT
TO LOOK PROPERLY
WORK
 PATHETIC
•
•
•
•
CONDITION OF ROADS
Defects in the quality of materials used.
Defects in construction methods and quality
control during construction.
Does not follow the correct geometric
standards.
Inadequate surface or subsurface drainage in
the locality resulting in the stagnation of water
in the sub grade or in any of the pavement
layers.
•
Increase in the magnitude of wheel loads and
the number of load repetitions due to increase
in traffic volume.
•
Settlement of foundation of embankment of the
fill material itself.
•
Environmental factors including heavy rainfall,
soil erosion, high water table, snow fall ,frost
action ,etc..
STEPS TO BE TAKEN FOR PREVENTING
ROAD ACCIDENTS….

Strict enforcement of speed limits.

One way traffic should be implemented.

Roads should be widened wherever required.

Curvatures should be minimized.

Footpaths and medians should be made
mandatory for all important roads.

Zebra crossing should be provided.

Provide signals, road markings, sign posts..

Construction of humps in important places,
PAVEMENT SAFETY FACTORS
 SURFACE
TEXTURE
 PAVEMENT
ROUGHNESS AND SURFACE
 PAVEMENT
SHOULDER DESIGN
DISTRESS
 RUMBLE
STRIPS
 PASSING
LANES
 TIME
OF DAY AND WEATHER CONDITON
 INCORPORATING
IMPROVEMENTS
ROAD SAFETY
SURFACE TEXTURE
 Road
surfaces must ensure an adequate level of
friction at the tyre pavement interfaces to
provide safe operation of vehicles.
 Pavement
•
•
surface properties
Micro texture – tyre pavement contact, skid
resistance
Macro texture –drainage ability
PAVEMENT ROUGHNESS AND SURFACE
DISTRESS

“potholes, bumps or ruts”.

Driving on roads in good condition, higher
accident may occur due to high speed, lower
skid resistance and some other safety factors.

Single and multiple vehicle accident rates.

To decrease single vehicle road accidents by

Multiple road accidents on rougher roads
contain two factors

Lateral variation in vehicle path

Road defects
PAVEMENT SHOULDER DESIGN
Shoulder performs variety of functions
o
Lateral support
o
Provides area
o
Provide easy driving
o
Safety zone for parking
o
Improve sight distance
Shoulder reduces accident rates for various lane
 Median
shoulder width increases, accidents
increases…
 Main
functions of traffic engineering studies is
to improve safety by
•
Minimizing shoulder drop-off
•
Increase driver comfort
•
Reduce property damage
RUMBLE STRIPS




Effective low cost method of providing
guidance for drivers.
Mainly helpful at the time of winter storms,
which reduces the visibility of pavement
marking.
Installed wherever the shoulder width is 2m or
more.
On shoulders adjacent to climbing lanes,
rumble strips may be installed on 1.5m
shoulder also.
PASSING LANES



Road system must have a wide paved lanes.
It helps in reducing problems during
overtaking and to avoid queues of vehicles on
the road.
It also provide adequate gap in the opposing
traffic nor absence of solid barrier lines.
TIME OF DAY AND WEATHER CONDITION
 These
are highly related to road accident rates.
 About
68% of accidents occur during daylight
hours while 27% occur during the hours of
darkness and the remaining 5% occur during
low light conditions.
 High
accident areas can be targeted with
innovative signing or reflectivity to ensure
drivers are aware of their environment.
INCORPORATING ROAD SAFETY
IMPROVEMENTS
 Pavement
engineering properties associated
with road safety, there are various treatments
available…

“skid resistance” can be restored by a list of
specific treatments such as.. ‘surface milling,
grooving, blasting, chip sealing, microsurfacing, slurry seal, planning, bush
hammering, etc..
 Also
based on pavement roughness, surface
condition evaluation, pavement performance
experience, surface visibility and paving
materials, etc..
CLASSES OF FACTORS & INDICATORS
MAINTENANCE TREATMENT & ROAD
SAFETY IMPROVEMENTS
ENGINEERING APPLICATIONS IN THE
FIELD OF TRANSPORTATION



Road safety is an integral part of engineering
design.
IRC formulates codes for road construction
,maintenance and also for road safety.
National highways used to be built through
PWDs, which connects the entire states of
nation.
MAJOR CHALLENGES PRETAINING TO
ENGINEERING MEASURES..
 Accessibility
 Economic
growth and development
 Deficiency
 Available
rather than mobility
of funds for non-NHDP networks
funds for maintenance & repair is
only about 35%-40% of the estimated fund
PRESENT POLICIES REGARDING
ENGINEERING MEASURES FOR ROAD
• SAFETY
Short term solutions
Inadequate provision of SSD, signage, shoulder width,
delineators, pedestrian railing, crash barriers, edge and
lane marking…..
•
Medium term solutions
Improvement of junctions, culvert parapet, lack of visibility
at night, safety measures for pedestrians, rest areas,
shoulder consolidation…..
GEOMETRIC DESIGN CONSIDERATIONS
OF ROADS TO PREVENT ACCIDENTS
Basic objectives of geometric design are

Optimize efficiency

Safety

Minimizing cost

Minimizing environmental damages

Livability
Geometric design can be broken into 3 parts

Alignment

Profile



ALIGNMENT- route of the road, defined as a
series of horizontal tangents and curves
PROFILE – vertical aspect of the road, including
crest, sag curves and the straight grade lines
connecting them.
CROSS SECTION – position, no of vehicles,
bicycle lanes and side walks ,along with their
cross slope or banking, drainage features,
DESIGN STANDARDS
 Design
guidelines taken into account by

Speed

Vehicle type

Road grade (slope)

View obstructions

Stopping distance
 AASHTO
published primary US guidance on “A
Policy on Geometric Design of Highway and
Streets” and other standards includes
PROFILE




Consist of road slopes(grades) connected by
parabolic vertical curves
Sag curves –tangent slopes at the end of the
curve that is higher than the beginning of the
curve
Crest vertical curves –tangent slope at the end
of the curve lower than the beginning of the
curve
Drainage – poor in sag curves and flat roads
SAG CURVES




Concave upwards
Head light sight distance (S)–important design
criteria
S is determined by angle of head light & angle
of tangent slopes at the end of the curve
Headlights are 2 ft above the ground and the
CREST CURVES


Convex upwards
Stopping sight distance is the important design
criteria, it is determined by the speed of traffic

Sight Distance > Curve Length (S>L)

Sight Distance < Curve Length (S<L)


US standards specify that, the height of driver’s
eye is up to 1080mm from the pavement and
height of object the driver needs to see as
600mm
Cyclist’s eye height is at 4.5 ft from the
pavement
GEOMETRY
CROSS SLOPE

Includes horizontal or lateral slopes

Leveled road creates problem of drainage

In tangent sections,1 – 2% C S is provided

“NORMAL CROWN” is provided

“SUPER ELEVATION” for curved sections

Lower cross slope increases, risk of loss of
control increases

8% super elevation is provided for sharp curves

Radius of curve is given by
SAFETY EFFECTS OF CROSS SECTION


Cross slopes and lane width affects the safety
performance of a road
‘lane departure crashes’ are mostly on narrow
lane roads
SIGHT DISTANCE

Length of road way ahead visible to the driver

It is the distance travelled during two phases
 Perception
reaction time
 Maneuver
time (Brake reaction time)
•
Depending upon the situations,3 types of sight
distance are used
 Stopping
sight distance
 Decision
sight distance



Stopping sight distance- distance travelled
during PRT & MT and affected by road
conditions, mass of the vehicle, inclination of
the road and some other factors
Decision sight distance- used when drivers
must make decisions more complex than stop
or don’t stop, roads are designed for DSD ,using
6 to 10sec for PRT & 4 to 5sec for MT
Intersection sight distance – distance needed to
safely proceed through an intersection ,it
CONCLUSION




Safety means first aid to the uninjured
Health of the nation is more important than the
wealth of the nation
Road safety is a major public health concern
Strict implementation of road safety measures
reduces the“ ROAD ACCIDENTS”
REFERENCES
Journal Articles:

DR. (Mrs.) Nishi Mittal & DR. S.M.Sarin,“
characteristics of road accidents in India”,
Indian Highways,October 2001

A. Anne Rosaline, B. Sathya Narayanan &
S. Shanmuga Sundara
Boopathy,“comparison of accident rate
using accident ranking”, Indian
Thank you