Rutting is one of the main cause for occuring distressed on the Surface of road. Also types and causess of Rutting are explained.

1. A seminar on
RUTTING IN FLEXIBLE
PAVEMENTS
Submitted by:
Prashant Hangal
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2. CONTENTS
1. INTRODUCTION
2. DEFINITION OF RUTTING
3. TYPES OF RUTTING
4. STUDY STRETCH
5. ENGINEERING PROPERTIES
6. RUT DEPTH MEASUREMENT TECHNIQUES
7. RUT MEASURING DEVICES
8. CAUSES OF RUTTING
9. MEASUREMENT OF PAVEMENT TEMPERATURE
10. CONCLUSIONS
11. REFERENCES2

3. OBJECTIVES
 To study the Types of Rutting and Preventive measures of
the same.
 To determine the nature and extent of rutting on
flexible pavements.
 To study the effect of high temperature of pavement layers
in compacted Bituminous mixes.
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4. INTRODUCTION
 Flexible pavements have been traditionally provided on most
of the important highways of the country.
 Bitumen as a binder is known to be highly sensitive to high
temperatures.
 Distresses in the form of ruts, cracking, ageing etc. are the
common ill effects observed on Flexible pavement.
 Rutting are more pronounced at locations of intersections,
curves and also where heavy traffic operates at low speed and
is subject to frequent stop/start condition.
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5. WHAT IS RUTTING….?
Rutting is one of the commonly observed
permanent type of natural distress in flexible
pavements due to failure of the subgrade.
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6. TYPES OF RUTTING
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Fig. 1 Instability Rutting
Fig 2 Rutting in Wheel Path Fig 3 Block Rutting

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Fig 4 Structural Rutting Fig 5 Fatigue Rutting
Fig 6 Sipplage Rutting

8. CASE STUDY
 The stretch considered is about 250 m long, suffering
Substantial rutting to a maximum depth upto 35 mm.
 This stretch is near an intersection. Heavy trucks with high axle
loads in large number (about 450 trucks per day) are operating
on this stretch, at a relatively low speed with frequent stop/start
condition.
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9. CONTINUED……
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10. CONTINUED…..
 The rut depth measurements has been done in the field using a
string line across the carriageway.
 Cores were taken from both rutted and fair locations.
 At rutted locations, the top layer of DBM (Layer II) was
observed to have undergone deformations, whereas BC layer,
in general, was not found significantly disturbed.
 The above observations reveal that the actual rutting is due to
permanent deformation in the DBM (Layer II), immediately
underneath the BC layer.
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12. RUT MEASURING DEVICES:
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 ROMDAS Linear Measurements

13. ROMDAS
ROMDAS® (ROad Measurement & Data Acquisition
System) has been developed by Data Collection Ltd. (DCL) as a
low cost modular system designed to collect road and pavement
data using any vehicle.
Linear Measurements
Rutting can be measured using a simple device, wherein
the rut depth will noticed vertically downwards. As this method is
simple to execute and it requires minimum two members to
execute the work.
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14. RUT DEPTH MEASUREMENTS
Pavement
Condition
Characteristics (traffic safety and impact on
the road user)
Rut Depth
limits (mm)
Very Good Pavement has no ruts. < 5
Good No ruts can be observed in the pavement and
there is no impact on road users.
5-10
Fair Ruts in the pavement can be observed. As rain
water gets accumulates in it. Ruts should be
eliminated within 1-3 years.
10-20
Poor Ruts can be clearly be seen in the pavement,
driving speeds are influenced.
20-30
Very Poor Ruts affect traffic safety both in rain and in dry
conditions.
> 30
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15. CAUSES OF RUTTING
Rutting in flexible pavement can occur due to variety
of causes such as:
 Inappropriate Mix Design.
 Incorrect grading
 Excessive Binder content
 Excessive fines like sand/clay
 Round aggregates with smooth texture
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16. CONTINUED….
 Inadequate initial field compaction and density.
 Effects of hot weather temperature on pavement.
 Effects of heavy traffic loads.
 Effect of slow speed (frequent stop/start or stationary
condition).
 Effect of secondary compaction.
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17. MEASUREMENT OF PAVEMENT TEMPERATURE
 Two different types of thermometers were used for
recording the temperature, which are duly calibrated
before the measurement.
I. Electrically Controlled Digital Thermometer
II. Ordinary Glass Mercury Thermometer.
 The temperature was measured at different locations
depth-wise in an increment of 20 mm.
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19. CONCLUSIONS
 The present case has attempted to examine the
adverse effects of high temperatures in top layers of
binder course.
 It demonstrates that, existing pavement design
method followed in India requires an early review and
upgradation to meet the different site conditions.
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20. REFERENCES
1. Superpave Mix Design Vol. I & Vol. II, Superpave series
No.1 & 2 (SP1 & SP2), Asphalt Institute, Lexington.
2. Specifications for Road and Bridge Works, MOSRT&H
(Fourth Revision 2001), IRC.
3. IRC:SP:53-2002 (First Revision) “Guidelines on Use of
Polymer and Rubber Modified Bitumen in Road
Construction”.
4. Asphalt Guide, Australian Asphalt Pavement Association
(AAPA) AUSTROADS Sydney 2002.
5. Highway Research Record No. 189 “Design Performance
and Surface Properties of Pavement (9 Reports)” 1967.
6. The Properties of Asphaltic Bitumen , Edited by J.PH.
Pffiffer, Elsevier Publishing Company, Inc. New York
Amsterdam, London Brussels
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