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GUJARAT TECHNOLOGICAL UNIVERSITY
Chandkheda, Ahmedabad
Affiliated
SMT.SHANTANEN HARIBAI GAJERA
ENGINEERING COLLEGE
A Report On-
SURVEY AND ANALYSIS OF ROAD PAVEMENT FAILURES
Under subject of
DESIGN ENGINEERING – 1
B. E., Semester – III
(CIVIL ENGINEERING)
Submitted by:
Group:
Sr. Name of student Enrolment No.
1. Malay B. Talaviya 161303106010
2. Shailesh C. Chavda 161303106002
3. Priyank B. Upadhyay 161303106011
4. Priyank Nakrani 161303106005
(Faculty Guide)
Academic year
(2016-2017)
CERTIFICATE
This is to Certificate That GTU
Enrolment No. Of Civil Engineering Department
from SMT.SHANTABEN HARIBHAI GAJERA ENGINEERING COLLEGE
has Completed Report on the Having Title "SURVEY AND ANALYSIS OF
ROAD PAVEMENT FAILURES", in Group Consisting of 3 Student under the
Guidance of the Faculty Guide
COUNTERSIGNED:-
Pro. Pro.
(Guide) Head of Department,
Civil Engineering. Dept., Civil Engineering. Dept.,
Smt.Shantaben Haribhai Gajera Smt.Shantaben Haribhai Gajera
Engineering College, Engineering College,
Amreli-365601 Amreli -365601
ACKNOWLEDGMENT
We acknowledges to our parents, Faculties & H.O.D, Institute
head and our friends for their humble help in completing this entire
project.
No work of significance can be claimed on result of an individual
effort and same holds true further for this project as well, for through it
carries our name the energy of many have contributed if no small
measure in completion of this project.
Team Members
1. Malay B. Talaviya 161303106010
2. Shailesh C. Chavda 161303106002
3. Priyank Nakrani 161303106005
4. Priyank B. Upadhyay 161303106011
CONTENTS
LIST OF FIGURES………………………………........................i
LIST OF TABLES………………………………………………iii
ABSTRACT ……………………………………………………..iv
CHAPTER 1 INTRODUCTION ………………………………………….1-7
1.1 Design of pavement 1
1.2 Types of Pavement Structure 2
1.3 Pavement Type 3
1.4 Causes of Pavement Failure 6
CHAPTER 2 DIFFERENT TYPE OF PROBLEM ……………………8-15
2.1 Fatigue cracking (Alligator cracking) 8
2.2 Longitudinal cracking 9
2.3 Transverse cracking 10
2.4 Block cracking 11
2.5 Edge cracking 12
2.6 Rutting 13
2.7 Potholes 13
2.8 De lamination 15
CHAPTER 3 CASE STUDY……………………………………………16-22
3.1 Introduction 16
3.2 Map 16
3.3 Problem 17
3.4 Reasons of problem 18
CHAPTER 4 SOLUTION…………………………………………...…23-33
4.1 Sealing versus Filling 23
4.2 Asphalt Resurfacing 25
4.3 Rejuvenation 26
4.4 Infrared Repair 28
4.5 Fog Seal (PASS) 29
4.6 Chip seal 30
4.7 Self-Adhering Waterproofing Membranes 31
4.8 Shallow Surface Repair (Pothole) 32
CONCLUSION………………………………………………...34
REFERENCES & BIBLOGRAPHY ………………………....35
i
LIST OF FIGURES
1.1 Design of pavement 1
1.2 Types of Pavement Structure 2
1.3 Time & Traffic 3 3
1.4 Time & Traffic 4 4
1.5 Time & Traffic 4 4
1.6 Time & Traffic 5 5
2.1 High severity alligator cracking 8
2.2 Longitudinal cracking 9
2.3 Low severity transverse crack 10
2.4 Medium to high severity block cracking 11
2.5 high severity edge cracking 12
2.6 Medium Severity Rutting 13
2.7 Potholes caused by poor drainage 14
2.8 Overlay de-lamination 15
3.1 Map of SH-34 16
3.2 Alligator Cracks 17
3.3 Transverse crack 18
3.4 Rainfall 20
4.1 Sealing 24
4.2 Basic Crack Repair Configurations 25
ii
4.3 Workers mill the existing asphalt surface in preparation for asphalt
resurfacing 26
4.4 Street sweeping with power broom 27
4.5 Application of Surface Treatment 27
4.6 Heating area to be repaired with Infrared machine 28
4.7 Adding new mix, heating and compaction 29
4.8 Application of PASS surface sealer on Metro Street 29
4.9 Proper spacing of emulsion and chip spreader 30
4.10 Chip seal placement 31
4.11 Self-Adhering Waterproofing Membranes 32
4.12 Shallow surface repair (Pothole) 33
iii
LIST OF TABLE
1 Traffic Survey 19
2 Average Rainfall in Amreli District 21
3 Guidelines for Crack Repairs 23
iv
A B S T R A C T
Generally it is observed that after the opening of newly constructed road or well maintained or
newly widened road which is very good in the terms of level of service, But it is after some
time with the use of traffic volume and constantly changing weathers, especially after monsoon
or in monsoon the road quality is decorated at every use of traffic and after some time it gets
completely decorated with uneven crack, pot holes, ruts, crack etc…. This problem is very
much common in every road. Hence the quality and level of service is dropped down drastically
as the road user increases but maintenance is overlooked.
Pavements fail prematurely because of many factors. There are four primary reasons pavements
fail prematurely, like Failure in design, Failure in construction, Failure in materials, Failure in
maintenance.
Here for case study we will pick one cluster of Amreli City, The district head quarter of Gujarat
state. In the case study we will find the problems, causes and remedies.
The key to proper maintenance of asphalt pavements is to understand the causes of failures and
the action needed for correction before any repair work is done. To make the most of
maintenance budgets, proven methods must be used to correct failures and to prevent their
recurrence.
According to the Foundation for Pavement Preservation, pavement maintenance involves
doing the right treatment, at the right place, at the right time. To achieve this, good management
and an understanding of the choices are required. The type of traffic plays very important role
for the life of pavement. The pavement design should be perfect, precise and with long future
vision of expected traffic in coming years. If the pavement is done perfectly as per design than
heavy maintenance is reduced & only periodical maintenance occurs.
If the pavement remains failure one and doesn’t maintained as per need than V.O.C ( vehicle
operating cost), Travel time, Traffic congestion, Traffic volume, Traffic density and lots of
Precious man hours / time is wasted.
So the pavement should be well maintained and good for smooth riding to road user which
overcomes the V.O.C, Traffic congestion, Traffic volume, Traffic density and precious man
hours.
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Chapter 1:- Introduction
1.1. Design of Pavement:-
The surface of the roadway should be stable & non-yielding, to allow the heavy
wheel load of road traffic to move with least possible rolling resistance. The road
surface should also be even along the longitudinal profile to enable the design speed.
The earth road may not be able to fulfil any of the above requirement, especially during
the varying conditions of traffic loads & the weather. At high moisture contents, the
soil becomes weaker & soft & starts yielding under heavy wheel loads, thus increasing
the tractive resistance discomfort & fatigue to the passengers of fast moving vehicle
& cyclists thus a pavement consisting of a few layers of pavement materials is
constructed over a prepared soil sub grade to serve as a carriageway.
Based on the vertical alignment & the environmental conditions of the site,
the pavement may be constructed over an embankment, cut or almost at the ground
level of the ground water to keep the sub grade relatively dry even during
monsoons.
Figure 1.1 Design of pavement
2
1.2. Types of Pavement Structure:-
Based on the structural behaviour, pavements are classified into two categories:
1.2.1. Flexible Pavements:-
Flexible pavements are those, which on the whole have low or negligible
flexural strength & are rather flexible in their structural action under the loads.
1.2.2. Rigid Pavements:-
Rigid pavements are those which possess noteworthy flexural strength or
flexural rigidity.
Figure 1.2. Types of Pavement Structure
3
1.3. Pavement Type:-
For paved roads there are five major pavement types, namely granular,
bituminous, concrete and cemented base pavements and pavements with paving blocks.
Unpaved roads constitute a separate pavement type.
1.3.1. Untreated granular-based pavements:-
This type of pavement comprises a thin bituminous surfacing, a base of
untreated gravel or crushed stone, a granular or cemented sub base and a subgrade of
various soils or gravels. The mode of distress in a pavement with an untreated sub
base is usually deformation, arising from shear or densification in the untreated
materials. The deformation may manifest itself as rutting or as longitudinal roughness
eventually leading to cracking.
Figure 1.3 Time & Traffic
1.3.2. Bitumen-base pavements:-
In bitumen-base pavements both deformation and fatigue cracking are possible.
Two types of sub base are recommended, namely either an untreated granular sub base
or a weakly stabilised cemented sub base. Rutting may originate in either the
bituminous or the untreated layers, or in both. This is illustrated in Figure. If the sub
base is cemented there is a probability that shrinkage or thermal cracking will reflect
through the base to the surfacing, especially if the bituminous layer is less than 150
mm thick or if the sub base is excessively stabilised. Maintenance usually consists of
a surface treatment to provide better skid resistance and to seal small cracks, an asphalt
overlay in cases where riding quality needs to be restored and when it is necessary to
prolong the fatigue life of the base, or recycling of the base when further overlays are
no longer adequate.
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Figure 1.4 Time & Traffic
1.3.3. Concrete pavements:-
In concrete pavements, most of the traffic loading is carried by the concrete
slab and little stress is transferred to the subgrade. The cemented sub base provides a
uniform foundation and limits pumping of sub base and subgrade fines. Through the
use of tied shoulders, most of the distress stemming from the edge of the pavement can
be eliminated and slab thickness can also be reduced. Distress of the pavement usually
appears first as spelling near the joints, and then may progress to cracking in the wheel
paths. Once distress becomes evident, deterioration is usually rapid.
Figure 1.5 Time & Traffic
5
1.3.4. Cemented-Base Pavements:-
In these pavements, most of the traffic stresses are absorbed by the cemented
layers and a little by the subgrade. It is likely that some block cracking will be evident
very early in the life of the cemented bases; this is caused by the mechanism of drying
shrinkage and by thermal stresses in the cemented layers. Traffic-induced cracking
will cause the blocks to break up into smaller ones. These cracks propagate through
the surfacing. The ingress of water through the surface cracks may cause the blocks
to rock under traffic, resulting in the pumping of fines from the lower layers. Rutting
or roughness will generally be low up to this stage but is likely to accelerate as the
extent of the cracking increases.
Figure 1.6 Time & Traffic
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1.4. Causes of Pavement Failure:-
Premature Failure:-
Pavements fail prematurely because of many factors. When boiled down to the basics,
there are four primary reasons pavements fail prematurely:
• Failure in design
• Failure in construction
• Failure in materials
• Failure in maintenance
1.4.1. Failure in Design:-
Most roads are not specifically designed. They have evolved from paths and trails to
the pavements we have today. This does not mean we need to go out and have a full-
blown engineering design done for every road repair. In fact, most roads work just fine.
However, there are still many issues that need to be examined. Do we understand the
conditions on the road? What is the traffic level? Has anything changed since the last
major improvement? Is anything likely to change? For low-volume roads, the most
important design challenge is accounting for weather and drainage conditions. If the
drainage is done correctly, and the road is built to certain minimums of thickness and
quality, it should hold up just fine. However, there are still many failures due to design.
Under-designed
Failure to account for conditions
Changes after construction
1.4.2. Failure in Construction:-
Just as design can lead to premature failure, poor quality construction can cause
a roadway to fail early. Many construction failures do not appear as defects for several
years, so it can be difficult to determine the reason for the failure. Whether the work is
done in-house or by contract, it is important to get the job done right. If you are doing
the work yourself, are you ready? Has the crew been trained? What training do they need
and where can you get the training? Municipalities have some of the best snow plow
crews anywhere. Part of that expertise is experience. You do something enough and you
get pretty good at it. Part of the expertise is training. Riding with that old-timer can be
some of the best training you can get. If you are contracting the work, are you ready? Do
you need an inspector for the work? Is the inspector trained and ready to make sure the
municipality gets what they pay for? What kind of contract are you using? Construction
may be the most difficult step because there are so many questions to be asked and
answered. The problem with not asking the questions is that we usually do not get a
second chance to do the work again. Fortunately, experience is a great
7
Teacher, and for most operations some basic training and practice is enough to make sure
the work is done right. Complicated and specialized work can still be problematic and
failures due to construction can occur.
Poor workmanship
Using incorrect equipment
Using equipment improperly
Failure to follow plans
Lack of training
Wrong time of year or poor weather
1.4.3. Failure in Materials:-
Using the wrong material in the right place or the right material in the wrong
place can lead to premature failure. Sometimes the problems are obvious. Sometimes the
problem does not appear to be related to the material choice. Backfilling an under drain
trench with large stone is actually a materials problem. The stones will retain silt particles
brought in by the drained water and will lead to premature plugging of the pipe. Be sure
to select the correct material for the job.
Wrong material
Material does not meet specifications
Material installed incorrectly
Incompatibility with other materials
1.4.4. Failure in Maintenance:-
The most common maintenance problem is that not enough maintenance is done.
This is a budgetary, planning, and communication issue that is sometimes very difficult
to overcome. Once we decide to perform maintenance we need to remember that ALL
maintenance techniques can be designed to fit the conditions and need to be constructed
properly using the correct materials. Premature failure of pavement maintenance is
usually a failure of design, construction, or material.
Design
Construction
Material
8
Chapter 2:- Different Type of Problem
1. Fatigue Cracking (Alligator Cracking):- Fatigue cracking is commonly called alligator cracking. This is a series of
interconnected cracks creating small, irregular shaped pieces of pavement. It is caused by
failure of the surface layer or base due to repeated traffic loading (fatigue). Eventually the
cracks lead to disintegration of the surface, as shown in Figure. The final result is potholes.
Alligator cracking is usually associated with base or drainage problems. Small areas may be
fixed with a patch or area repair. Larger areas require reclamation or reconstruction. Drainage
must be carefully examined in all cases.
Figure 2.1 High severity alligator cracking
9
2. Longitudinal Cracking:-
Longitudinal cracks are long cracks that run parallel to the canter line of the
roadway. These may be caused by frost heaving or joint failures, or they may be load induced.
Understanding the cause is critical to selecting the proper repair. Multiple parallel cracks may
eventually form from the initial crack. This phenomenon, known as deterioration, is usually a
sign that crack repairs are not the proper solution.
Figure 2.2 Longitudinal cracking
10
3. Transverse Cracking:-
Transverse cracks form at approximately right angles to the centreline of the
roadway. They are regularly spaced and have some of the same causes as longitudinal
cracks. Transverse cracks will initially be widely spaced (over 20 feet apart). They usually
begin as hairline or very narrow cracks and widen with age. If not properly sealed and
maintained, secondary or multiple cracks develop, parallel to the initial crack. The reasons
for transverse cracking, and the repairs, are similar to those for longitudinal cracking. In
addition, thermal issues can lead to low-temperature cracking if the asphalt cement is too
hard. Figure shows a low-severity transverse crack.
Figure2.3 Low severity transverse crack
11
4. Block Cracking:-
Block cracking is an interconnected series of cracks that divides the pavement
into irregular pieces. This is sometimes the result of transverse and longitudinal cracks
intersecting. They can also be due to lack of compaction during construction. Low severity
block cracking may be repaired by a thin wearing course. As the cracking gets more severe,
overlays and recycling may be needed. If base problems are found, reclamation or
reconstruction may be needed. Figure shows medium to high severity block cracking.
Figure 2.4 Medium to high severity block cracking
12
5. Edge cracking:-
Edge cracks typically start as crescent shapes at the edge of the pavement.
They will expand from the edge until they begin to resemble alligator cracking. This type
of cracking results from lack of support of the shoulder due to weak material or excess
moisture. They may occur in a curbed section when subsurface water causes a weakness
in the pavement. At low severity the cracks may be filled. As the severity increases, patches
and replacement of distressed areas may be needed. In all cases, excess moisture should
be eliminated, and the Shoulders rebuilt with good materials. Figure shows high severity
edge cracking.
Figure 2.5 high severity edge cracking
13
6. Rutting:- Rutting is the displacement of pavement material that creates channels in the wheel
path. Very severe rutting will actually hold water in the rut. Rutting is usually a failure in
one or more layers in the pavement. The width of the rut is a sign of which layer has failed.
A very narrow rut is usually a surface failure, while a wide one is indicative of a sub grade
failure.
Inadequate Compaction can lead to rutting. Figure shows an example of rutting due
to sub grade failure. Minor surface rutting can be filled with micro paving or paver-placed
surface treatments. Deeper ruts may be shimmed with a truing and levelling course, with
an overlay placed over the shim. If the surface asphalt is unstable, recycling of the surface
may be the best option. If the problem is in the sub grade layer, reclamation or
reconstruction may be needed.
Figure 2.6. Medium Severity Rutting
7. Potholes:-
Potholes are bowl-shaped holes similar to depressions. They are a progressive
failure. First, small fragments of the top layer are dislodged. Over time, the distress will
progress downward into the lower layers of the pavement. Potholes are often located in
areas of poor drainage, as seen in Figure Potholes are formed when the
14
pavement disintegrates under traffic loading, due to inadequate strength in one or more
layers of the pavement, usually accompanied by the presence of water. Most potholes
would not occur if the root cause was repaired before development of the pothole. Repair
by excavating and rebuilding. Area repairs or reconstruction may be required for extensive
potholes.
Figure 2.7 Potholes caused by poor drainage
15
8. De-lamination:-
De-lamination is a failure of an overlay due to a loss of bond between the overlay and
the older pavement. Common causes of de-lamination include: wet or dirty surface during
paving of the overlay, failure to use a tack coat, or poor compaction of the overlay. Proper
paving techniques, including cleaning the surface and use of tack coat, will reduce the chances
of de-lamination.
Figure 2.8 Overlay de-lamination
16
Chapter 3:- Case Study
3.1. Introduction:-
Amreli is a small city in Gujarat& it’s a district head quarter. The peninsula
extends southwest into the Arabian Sea and is bounded on the northwest by the Gulf of
Kachchh and on the southeast by the Gulf of Khambhat. Area, about 60,000 km² (about
23,000 sq. mi).Amreli has variety of lands like Medium black, loamy, sandy, and rocky.
Main crop of this province is Cotton & Other local crop like Bajra, Wheat, sugar cane &
Vegetables & in Fruits Main Is Mango.
Amreli is located in Saurashtra region of Gujarat state with 20°45" to 22°15" North
Latitude and 70°13" to 71° 45" East Longitude. It falls under the North Saurashtra Agro
Climate Zone of Gujarat.
The regional transport system of Amreli is essentially a road based system. The city of
Amreli is connected to other parts of the country through a developed regional road (state
highway and District Roads) system.
3.2. Map:-
Figure 3.1 Map of SH-34
17
3.3. Problem:-
Our case study on SH-34 (Amreli city).we will see in our study most common
problem is Alligator Cracking and Transverse cracking. Main reason of road creaking is
heavy loading vehicles passing on road. 24X7 hours transport heavy loading vehicles on
road.
Figure 3.2 Alligator Cracks
18
Figure 3.3 Transverse crack
3.3. Reasons Of Problem:-
3.3.1. Traffic:-
Traffic is the most important factor influencing pavement performance.
The performance of pavements is mostly influenced by the loading magnitude,
configuration and the number of load repetitions by heavy vehicles. The damage
caused per pass to a pavement by an axle is defined relative to the damage per
pass of a standard axle load, which is defined as an 80 kN single axle load (E80).
Thus a pavement is designed to withstand a certain number of standard axle load
repetitions (E80’s) that will result in a certain terminal condition of deterioration.
Road Sections having relatively heavy traffic of more then 7000 P.C.Us
per day either in April or October or both round of Traffic Census – 2014
19
ROAD SH-34
District Amreli
Width of Carriage Way (Mt.) 10.00
Auto Riksha April October
652 685
Car Old Tech. April October
653 686
Mini Bus April October
1451 1523
Std Bus April October
1335 1402
LCV April October
1358 1415
2-XL Truck April October
680 713
3-XL Truck April October
1514 1589
M-XL Truck April October
1337 1406
Two Wheeler April October
1766 1853
Sub Total (6-17) April October
2034 2136
Tract with Trailer April October
519 498
Tract without Trailer April October
475 498
Animal Driven Vehicle. April October
13772 14403
Grand Total (18+19) April October
13794 14405
Table 1. Traffic Survey
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3.3.2. Rainfall:-
Rainfall is most of the common factor pavement failure. Since past 10
Years the average rainfall in this area has increased unexpectedly so exisisting
roads are not designed according that intensity of rain. Moisture can significantly
weaken the support strength of natural gravel materials, especially the sub grade.
Moisture can enter the pavement structure through cracks and holes in the surface,
laterally through the sub grade, and from the underlying water table through
capillary action. The result of moisture ingress is the lubrication of particles, loss
of particle interlock and subsequent particle displacement resulting in pavement
failure.Average rainfall of Amreli city is 552mm.
Figure 3.4 Rainfall
21
Sr. No. Year
Average rainfall at
Amreli Head Quarter
(In M.M.S.)
Average rainfall in Amreli
district (in M.M.S.)
1 2005 709 578.6
2 2006 414 447.8
3 2007 234 306.9
4 2008 509 541.5
5 2009 573 559
6 2010 667 676.3
7 2011 413 601.4
8 2012 1223 1088
9 2013 1167 823.8
10 2014 1357 1069
Table 2. Average Rainfall in Amreli District
578.6
447.8
306.9
541.5 559
676.3
601.4
1088
823.8
1069
0
200
400
600
800
1000
1200
Average rainfall in Amreli district (in M.M.S.)
Average Rainfall In Amreli District (In M.M.S.)
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
22
3.3.3 Construction Quality:-
Failure to obtain proper compaction, improper moisture conditions
during construction, quality of materials, and accurate layer thickness (after
compaction) all directly affect the performance of a pavement. These conditions
stress the need for skilled staff, and the importance of good inspection and
quality control procedures during construction.
3.3.4. Maintenance:-
Pavement performance depends on what, when, and how maintenance
is performed. No matter how well the pavement is built, it will deteriorate over
time based upon the mentioned factors. The timing of maintenance is very
important, if a pavement is permitted to deteriorate to a very poor condition, as
illustrated by point B in Error! Reference source not found. Then the added life
compared with point A, is typically about 2 to 3 years. This added life would
present about 10 percent of the total life. The cost however of repairing the road
at point B is minimum four times the cost if the road had been repaired at point
A. The postponement of maintenance hold further implications, in that for the
cost of repairing one badly deteriorated road (Point B), four roads at point A
would have to be deferred, which would mean that in a few years the
rehabilitation cost could be 16 times as much. Thus, postponing maintenance
because of budget constraints, will result in a significant financial penalty within
a few years. Amreli municipal corporation is small, they are can’t maintenance
daily, so create problem.
23
Chapter 4:- Solution
Crack repairs are the proper and timely maintenance of cracks using sealing or
filling techniques to extend pavement life. Crack repairs are very cost effective if done properly.
A crack repair program begins by determining if crack repairs are suitable for the type of
distress.
4.1. Sealing versus Filling:-
There are two distinct techniques used to repair cracks: sealing and filling.
• Crack sealing
The placement of specialized materials either above or into working cracks
using unique configurations to prevent the intrusion of water and debris into the crack.
Working cracks are defined as those that experience significant horizontal movements,
generally greater than about 1/8 inch over the course of the year. Working cracks are
generally more widely open during winter months, and less open in summer months.
Cold weather causes the pavement surface to contract, which opens the cracks.
• Crack filling
The placement of materials into nonworking cracks to reduce infiltration of
water and to reinforce the adjacent pavement.
It is important to remember that sealing uses more flexible materials than filling. This
allows the seal to move with the crack. Sealing material is more expensive, but is
usually worth the extra money. Substantial savings can result if the cracks are not
moving.
Showing table the basic guidelines for choosing between crack sealing and crack filling.
Crack
Characteristics Sealing Filling
Crack width 1/4" to 3/4" (5 to 19 mm) 1/4" to 1" (5 to 25 mm)
Edge deterioration
(spalls, secondary
cracks)
Minimal to none
(equal to or less than 25%
of crack length)
Moderate to none
(equal to or less than 50%
of crack length)
Annual horizontal
Movement equal to or less than 1/8" (3 mm) less than 1/8" (3 mm)
Type of crack
• Transverse thermal
• Transverse reflective
• Diagonal
• Working longitudinal
• Longitudinal reflective
• Longitudinal cold joint
• Longitudinal edge
• Distantly spaced block
Preparation
• Routing/sawing
• Cleaning/drying
• Backer rod (if required)
• Blowing out debris
Table 3. Guidelines for Crack Repairs
24
Figure 4.1 Sealing
4.1.1. Materials:-
Various materials can be used to repair cracks. There are many different
desirable characteristics. All crack repair materials need to have good adhesion to
the sides of the crack. Installation and performance issues are also factors that
need to be examined the desirable properties of the various materials. The most
commonly used crack treatment materials and provides recommendations for use,
as well as basic cost information. As a general rule, materials that are more
flexible will perform better in sealing operations. Polymer and rubberized
materials have shown the best performance.
4.1.2. Configuration:-
Crack repair material is placed in a specific configuration that is most
suitable for the application. Three basic configurations are shown in Figure. There
are many other specialized configurations, but they are all variants or
combinations of the three shown.
25
Over band
Flush-Fill Reservoir
Figure 4.2 Basic Crack Repair Configurations
4.1.3. Limitations:-
Crack repairs do not restore the structural integrity of the pavement.
They can improve the strength of the pavement during wet periods, such as
spring thaw, by eliminating or reducing the inflow of water under the
pavement.
Cracks should be sealed when they are at the middle of their
working range. This allows the cracks to expand and contract with less
stress on the sealant. A sunny day in spring or fall is a very good time to
seal cracks, if all of the other weather factors are favourable.
4.2. Asphalt Resurfacing:-
Asphalt surfaces have a typical service life of 8 to 12 years, depending on
traffic and weather conditions. Asphalt resurfacing is necessary when the asphalt
surface has reached the end of its service life or if other methods of restoration cannot
repair the roadway. A new asphalt surface will improve driving conditions as well as
the aesthetics of the roadway. Asphalt resurfacing is a multi-step process that usually
involves several work crews, accompanied by proper construction signs and work-zone
traffic control measures to maintain public safety. Resurfacing an asphalt roadway
requires the following steps:
Adjustment (lowering) of utilities to allow milling machines to traverse the roadway
without damaging utility assets.
Removal (milling) of old surface using a milling machine. All milled surfaces must
be cleaned by the milling contractor and marked appropriately to safely direct
traffic. (Milling may not be required on streets with no curb and gutter; however, the
edges of streets with no curb and gutter may be trimmed prior to milling in order to
provide a more uniform milled surface.)
26
Re-adjustment (raising) of utilities so that they will again be flush with the new
surface that will be applied.
Application of a tack coat to milled surface to serve as a binder for the new surface
that will be applied.
Application of new paving surface by paving machines.
Application of new thermal plastic pavement markings on new pavement surface.
Below are pictures of the asphalt resurfacing process.
Figure 4.3 Workers mill the existing asphalt surface in preparation for asphalt
resurfacing
4.3. Rejuvenation:-
Rejuvenation is a preventive maintenance technique applied to newly paved
streets to replenish lighter oils and rejuvenate the roadway in order to prolong its service
life. Because the cost of applying surface treatments is minimal compared to resurfacing
the roadway, Metro makes an effort to utilize surface treatments to extend the service
life of streets throughout on County Rejuvenation Process includes following steps:
Before surface treatment can be applied, the roadway must be cleaned. A power
broom is used to clean the roadway surface.
The surface treatment will be applied from a distributor truck.
Workers will manually spray corners and hard to reach areas.
The street will be covered with a layer of sand for approximately 24 hours while the
surface treatment cures.
The sand will be swept by the contractor.
Below are pictures of the surface treatment process.
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4.4. Infrared Repair:-
A technique where infrared heating systems apply heat to pavement surfaces and
aid in the removal of existing material and replacement with new asphalt mixture.
Infrared thermal bond bituminous pavement patching is a method of blending new
asphalt mix with infrared heated existing blacktop pavement to create a joint-free integral
patch. A special machine is used to heat the existing blacktop to a depth of approximately
two inches without oxidation or burning. There is no flame in direct contact with the
existing blacktop surface. The unit is also equipped with chambers which are capable of
storing up to four tons of fresh bituminous materials at a consistent temperature.
Infrared Repair includes following steps:
Before repair can be made the area must be heated with infrared machine.
New mix is added.
The new mix is heated with the infrared machine.
The repair are is compacted.
Below are pictures of the infrared repair process.
Figure 4.6 Heating area to be repaired with Infrared machine
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Figure 4.7 Adding new mix, heating and compaction
4.5.Fog Seal (PASS):-
PASS emerged in the test sections as a good material to minimize ravelling and
extend lifetime of roadways that were last paved 8 to 9 years back. PASS is polymer
modified asphalt surface sealer applied as a fog seal. The image below shows the
application of PASS on Metro roadways. PASS lets Metro Nashville extend a
roadway’s lifetime by about 5 years before resurfacing is needed.
Figure 4.8 Application of PASS surface sealer on Metro street
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4.6. Chip seal:-
Also known as a surface treatment, a chip seal is a layer of asphalt emulsion
covered by a layer of single-sized aggregate. Timing of the construction, and the weather
during construction, have major influences upon the success or failure of a chip seal.
Chip seals will be discussed in more detail later in this chapter. Figure shows the proper
spacing between the laying of the emulsion and the chip spreader during a chip sealing
operation.
Figure 4.9 Proper spacing of emulsion and chip spreader
Chip seals are the most common thin wearing course. Many of their details are
applicable for all other wearing courses.
This section is not intended to cover everything about chip seals, it is merely guide to help
explain the process and the most critical factors involved. Additional training and experience
is needed for someone to become an expert. If you are interested in training your crew, check
with a local in a chip seal, an asphalt emulsion is sprayed on a cleaned road surface, and
immediately spread with a layer of single-sized stones. The stones are then rolled. This
orients and seats them within the emulsion layer. Figure illustrates these steps. A few days
later the surface is lightly boomed to remove any loose aggregate.
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Figure 4.10. Chip seal placement
4.6. Self-Adhering Waterproofing Membranes:-
As a pavement ages, imperfections appear, joints become prominent and cracks
occur, allowing water to infiltrate into and weaken the sub grade causing even more
damage to the pavement. Asphalt overlays are commonly used over asphalt and concrete
surfaces to extend the life of the pavement and reduce the effects of aging, saturated sub
grade and fatigue. Eventually, the process will repeat itself, as cracks and joints reflect
through the new overlay.
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Figure 4.11 Self-Adhering Waterproofing Membranes
4.7. Shallow Surface Repair (Pothole):-
• Usually the result of loss of bonding
• Seldom deeper than 50 mm if repaired in time
Method
• Identify, mark, excavate and clean to 75 mm deep
• Cover entire exposed area with bitumen emulsion tack coat(Especially edges)
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• Place asphalt (HMA or CMA) in hole and rake level (just above road level)
• Compact with hand tamper, plate compactor or roller
• Sweep all loose material from the patch area
• Blind with sand if required and open to traffic
• Check for level (see QC requirements)
• Seal joins with geo-synthetic strip and blind entire Patch with sand (< 4.75 mm)
Figure 4.12 Shallow surface repair (Pothole)
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CONCLUSION
After referring the literature survey & theory concept of pavement failure we can come on
following conclusion......Which can help to improvise the quality of maintenance & minimise
the number of repairing.
The pavement should be designed with precise future forecasting.
The pavement should be constructed as per design only.
The pavement should be maintained periodically...i.e. On the maintenance concept of
routine, Periodic & complete maintenance.
The road user should be as per consideration only...if the nature of traffic changes due
to unexpected growth of the area than it should be well maintained.
There should not be any delay in maintenance.
The nature of traffic plays vital role for the life span of pavement so at the time of
designing assumption of the future traffic is very much important.
The authority should adopt the modern Or latest technology in maintenance.
The modified maintenance equipment should be used for batter result Or to minimise
the maintenance or Increase the life cycle of pavement with batter service to the road
user.
Adoption of maintenance should be based on the type of problem of pavement failure
and the most appropriate treatment should be preferred.
The treatment should be such a good way that it minimise the maintenance of
pavement.
The maintenance should be done in off peak hours or in odd hours so the traffic is
least affected.
The suitable weather should be preferred at the time of maintenance of pavement.
The use of material for the maintenance should be of batter quality & appropriate
according to the topography and situation.
The safety standards to be maintained at the time of maintenance by the worker by
wearing safety goods and warning sign boards are to be placed at working area so the
traffic can be regularised in smooth way.
At the time of maintenance the used material or the treatment for maintaining the
pavement should be environment friendly.
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REFRENCES & BIBLOGRAPHY
A Text Book of Transportation Engineering By S. P. Chandola.
Roads, Railways, Bridges & Tunnel Engineering By G. S. Birdi.
Traffic Engineering & Transport Planning By L. R. Kadiyali.
Highway and Airport Engineering by V. B. Priyani.
Highway and Airport Engineering by S. C. Rangwala.
Transportation Engineering &Planning. 3/Edi. By Papacostas&Prevedouros.
Highway Engineering by Khanna & Justo.
Different websites....
www.google.com
www.neptl.org.in
https://www.google.co.in/solutionforpavementfaillure
https://www.google.co.in/rigidpavementfailure
http://newtecumseth.ca/town-hall/departments/public-works/pavement-repairs
https://www.penhall.com/technical-guides/pavement-repair-methods/