IRC-H-6-IRC-82-Final-Draft-15.01.2015.docx

7/25/2019 IRC-H-6-IRC-82-Final-Draft-15.01.2015.docx

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First Revision of

Code of Practice for Maintenance of

Bituminous Road Surfaces (IRC: 82)

Indian Roads Congress

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Section 1

Introduction

(To be added by IRC)

Section 2

Scope

21 By early detection of distress and appropriate repair of bituminous surface at initial stages,

further deterioration of the pavement surface can be prevented or delayed. This code of

Practice deals only with the Routine!, Preventive! and Periodic! maintenance of

bituminous surfaces.

22 "everal phases are involved in underta#ing maintenance operations for bituminous surfaces

as discussed in subse$uent sections. "ection % and & deals with importance and types of

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maintenance. 'aintenance Planning and system approach for maintenance are described in

"ections ( and , respectively. Types of pavement distresses, identification, severity, their

causes, and methods of treatment are given in Section 7.

2! Preventive maintenance is need of the day and is described insection 8. Periodic renewals

are covered in Section 9. Sections, *+, **, *, and *% deal with the materials and methods

for rectification, tools and e$uipment, arrangements for traffic, and organi-ation and

management, respectively.

2" perations falling in the category of pavement rehabilitation and strengthening are beyond

the scope of this code of practice. /or design of rehabilitation and strengthening measures

for e0isting pavements, reference may be made to the following publications.i) IRC12* 3uidelines for "trengthening of /le0ible Road Pavement using Ben#elman

Beam 4eflection Techni$ue!

ii) IRC1%5 Tentative 3uidelines for the 4esign of /le0ible Pavements!iii) IRC1**( 3uidelines for "tructural 6valuation and "trengthening of /le0ible

Pavement using /alling 7eight 4eflectometer, as the case may be.

Section !

Importance of Maintenance

The timely up#eep and maintenance of bituminous surfacing offers numerous benefits for

preservation of road asset. The importance of overall maintenance is described below1

i) Reduction in rate of deterioration and improvement in life of road

ii) Reduction in 8ehicle peration Costs 98C)

iii) Reduction in rate of accidentsiv) :eeping traffic worthy roads in all weather

v) Reduction in pollution by reduced fuel consumption

vi) "avings in budgetary e0penditure of restoration; reconstructionTimely and regular maintenance of roads have been #nown to provide economic rate of return

as high as *( to + percent depending upon the category of road and traffic volume. 'oreover,

it helps in deferring the demand for rehabilitation which otherwise is far more costlier than

preventive maintenance. Therefore, timely and appropriate maintenance of bituminous surface

using sustainable; suitable materials and methods is significant for preservation of road asset

and to serve the intended purpose.

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Section "

#$pes of Maintenance

'aintenance operations covered in this Code of Practice are classified into three broad

categories

(a) Routine Maintenance: This covers items such as filling of potholes, repairing of crac#s and

patch wor#, which are underta#en by the maintenance staff almost round the year

(b) Preventive Maintenance: The preventive maintenance is performed to improve or e0tend

the functional life of pavement surface while in good condition. This may defer the need of

periodic maintenance and rehabilitation.

(c) Periodic Maintenance: This includes regular maintenance operations compared to

preventive maintenance such as applying a renewal coat, which are re$uired to be done

periodically at the specified fre$uency or based upon condition and performance of road

surface depending upon category of road, traffic and climatic conditions.

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Section %

P&anning of Maintenance 'ctivities

(.* ) ?*+ (.+ to *+.+ @(

Raveling 9>) ?*+ *.+ to *+.+ @*

Potholes 9>) ?*.+ +.* to *.+ @+.*

"hoving 9>) ?*.+ +.* to *.+ @+.*Patching 9>) ?*+ * to *+ @ *.+

"ettlement and

4epression 9>)

?( * to ( @ *.+

Rut depth 9mm) using

% m straight edge

?*+ (.+ to *+.+ @(.+

Rating, Aumber * *.* .* %

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Condition Poor /air 3oodNotes: The various distressdefects t!pes as mentioned above to be observed visua""! as described

in Appendix 1 and to be noted in a standard proforma as #iven in Proforma 1$

#a&e %2 Pavement istress Based Rating for MR and Rura& Roads (-R and .R)

efects Range of istress

Crac#ing, 9>) ?+ *++ @ *+.+

Raveling, 9> ) ?+ *++ @*+

Pothole, 9>) ?*.+ +.( to *.+ @+.(

Patching, 9>) ?+ (+ @(.+

"ettlement and depression, 9>) ?( to ( @.+

Rating * *.* .* %

Condition Poor /air 3ood

#a&e %! Pavement istress Based Rating for /ran Roads

efect Range of istress

Crac#ing, > ?*( (*( @(.+

Raveling, > ?*+ ( to *+ @(

Potholes, > ?+.( @+.( A may be considered as bleeding; fatty surface of low severity. "ometimes bleeding;fatty

surface is confined to entire lane along with wheel path. In case the area is in the range of * to (>,

it may be treated as fatty surface; bleeding of medium severity. 60tensive bleeding and fatty surface

showing initiation of shoving shall be treated as fatty surface of 60tensive "everity!. P+otos

5..*, 9a,b,c) indicate low, medium and e0tensive severity level of bleeding and fatty surface

respectively.

(a) o, severit$ () Medium severit$ (c) *ig+ severit$

P+oto 421 B&eeding

421% #reatment

(a) o, Severit$: 'inor bleeding ; low severity fatty surface can be corrected by applying heated

coarse sand 9passing *.*2 mm sieve) to blot up e0cess bitumen in affected area followed by light

rolling.

() Medium Severit$: 'edium severity bleeding and fatty surface may be corrected by

application of precoated chipsH Passing &.5( mm and retained over *.*2mm using * > bitumen

and generally applied in a single layer followed by light rolling. In case the layer of bleeding is less

than * mm, treatment described for low severity would be sufficient.

(c) *ig+ Severit$: The affected portion shall be milled out and repaired with mi0 of desired

$uality. The milled material i.e Recycled


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premi0 carpet with low bitumen content can also be applied to absorb the e0cess binder. In the case

of large areas of fatty surface, having irregularities, removal of the affected layer and replacing it

with a layer of properly designed mi0, may be necessary.

422 Smoot+ surface

4221 S$mptoms

< smooth surface has a low s#id resistance and becomes very slippery when it is wet. "uch a

condition invites ha-ards, especially on gradients, bends, and intersections, Photo 422indicates a

smooth surface.

Photo 422 ' vie, of smoot+ surface

4222 ocation

"mooth surface may be restricted to a lane; carriageway.

422! Causes

< primary cause for a smooth surface is the polishing of aggregates under traffic. 60cessive binder

can also contribute to formation of smooth surface.

422" Severit$ eve&s

The severity level of smooth surface may be defined by s#id number. < surface with s#id number in

the range of %+ to &+ indicates low severity smooth surface while s#id number below %+ indicates

high severity smooth surface.

422% #reatment

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The rectification consists of resurfacing with a surface dressing course or a premi0 carpet or

microsurfacing depending upon type of e0isting surface. Care should be ta#en to select aggregates

which have proven nonpolishing characteristics. The carpet can be an open graded mi0. < slurry

seal can also be used to impart anti s#id te0ture on a smooth surface.

42! Strea6ing

42!1 S$mptoms

"trea#ing is characteri-ed by the appearance of alternate lean and heavy lines of bitumen either in

longitudinal direction or a transverse direction. Photo 5..%. shows strea#ing.

P+oto 42! Strea6ing of Bituminous Pavement

42!2ocation

"trea#ing may occur in a lane or carriageway.

42!! Causes

Fongitudinal strea#ing results when alternate longitudinal strips of surface contain different

$uantities of bitumen due to nonuniform application of bitumen across the surface. "ome of the

more common causes of strea#ing are mechanical faults, improper or poor ad=ustment and careless

operation of bitumen distributors. These strea#s can also be formed as a result of applying the

bituminous binder at too low temperatureH a temperature at which bitumen is not fluid enough to be

delivered uniformly smooth flow from the no--les on the spray bars.


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The satisfactory repair for longitudinal and transverse strea#ing is to remove the strea#ed surface

and apply a new surface. It is always desirable to prevent longitudinal and transverse strea#ing than

to correct it. 7henever mechanical e$uipment is used for spraying of bitumen, distributor should be

carefully adhered to.

42" *ungr$ surface

42"1 S$mptoms

ungry surface is characteri-ed by the loss of fine aggregates from the surface or the appearance of

dry surface with fine crac#sH Photos 5..& indicate a dry and hungry surface

P+oto 42" .ie, of dr$ and +ungr$ surface

42"2 ocation

ungry surface may be in full lane or carriageway.

42"! Causes

ne of the reasons for hungry surface is the use of less bitumen in the surfacing. "ometimes this

condition may also appear due to use of absorptive aggregates in the surfacing.

42"" Severit$ eve&s

Aot applicable

42"% #reatment

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/og seal ; li$uid re=uvenating materials may be used for correction of dry and hungry surface.

"lurry seal or microsurfacing may also be used as a repair measure, when applied in an average

thic#ness of & mm.

4! Crac6s

4!1 enera&

Crac#ing of bituminous surfacing is a common distress seen on ma=ority of roads in India 9with the

passage of time). Crac#s in bituminous surface are classified into various types depending upon

severity. Immediate attention must be given for sealing of crac#s, and prevention of their further

widening as ingress of water through crac#s is detrimental to pavement structure and performance

of bituminous surfacing.

4!2 *air&ine Crac6s

4!21 S$mptomsairline crac#s are present in narrow area and their width is less than one mm 9Photo 5.%.*).

airline crac#s are generally isolated and normally these are not interconnected. These appear as

short and fine crac#s at close intervals on the surface. "uch crac#s many a times disappear in hot

summer.

P+oto 4!1 *air&ine crac6s

4!22 ocation

These crac#s may be at isolated places or in a lane; carriageway.

4!2!Causes

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These crac#s develop due to either insufficient bitumen content, e0cessive filler, improper

compaction o0idation of bitumen in surface or sometimes e0cessive moisture in granular layers.

These may occur due to rolling of mi0 while it is still tender or e0cessive compaction.

4!2" Severit$ eve&s

Aot applicable

4!2% #reatment

These crac#s may be treated by fog seal, application of li$uid re=uvenating agents, slurry sealing

and microsurfacing.

4!! '&&igator and Map Crac6ing

4!!1 S$mptoms


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o, Severit$ Fow severity crac#s are characteri-ed by an area of crac#ing with very narrow

crac#s with almost no additional deterioration of the surface. The crac#ing is often isolated and

many times, the crac#ing may not be interconnected to other areas and there is not much distortion.

The depth and width of such crac#s is in the range of * to %mm.

Medium Severit$: 'edium severitycrac#ing is characteri-ed by interconnected crac#s forming a

small area similar to the s#in of alligator. The crac#s may have signs of slight spalling, with no

pumping visible. The depth and width of such crac#s lies between % to mm.

(a) o, severit$ () Medium severit$ (c) *ig+ severit$

P+oto 4!2 '&&igator crac6s

*ig+ Severit$: igh "everity alligator crac#ing is characteri-ed by an area of moderate to severely

spalled interconnected crac#s creating a full pattern of crac#ing similar to the s#in of an alligator.

The width and depth in this case may be more than mm. Pieces of bituminous surface may be

loose or missing. The pumping of water and fine material below the pavement may be seen on the

surface.

4!!% #reatment

In order to repair a pavement affected by alligator crac#ing, the main cause of the crac#ing should

be determined. owever, often the specific cause is fairly deep seated.


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c) 'illing and surface recycling

In case of a pavement being structurally inade$uate;wea#, a properly designed overlay based on

evaluation shall be provided

4!" ongitudina& Crac6ing

4!"1 S$mptoms

Crac#s appear parallel to the centerline or along the road are called longitudinal crac#s. These

crac#s are also sometimes source of onset of alligator crac#ing.

(a)o, severit$ () Medium severit$ (c) *ig+ severit$

P+oto 4!!: ongitudina& crac6ing

4!"2 ocation

These crac#s may appear at =oints between two paving lanes or pavement and paved shoulders.

4!"! Causes

Fongitudinal crac#s in bituminous pavement are usually caused by alternate wetting and drying

beneath the shoulder surface or by improper;wea# =oint between ad=oining layers of pavement.

4!"" Severit$ &eve&

"everity of longitudinal crac#s may be defined as low, 'edium and high. 9Photos 5.%.%1 a, b and c)

The low severity is assigned to *% mm wide and infre$uent crac#s medium severity is assigned to

% mm wide. igh "everity is assigned to crac#s greater than mm wide and are fre$uent

9numerous).

4!"% #reatment

Treatment for longitudinal crac#s depend upon the severity and e0tent of the crac#ing 1

9a) Fow and medium "everity Crac#s. Crac# sealing, preferably using rubberised bitumen

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9b) igh "everity Crac#s. Remove and replace the crac#ed pavement layer with fresh

overlay.

4!% #ransverse Crac6s

4!%1 S$mptoms

These crac#s appear in the transverse directions or as interconnected crac#s forming series of large

bloc#s perpendicular to the direction of the road.

(a) o, severit$ (a) Medium severit$ (c) *ig+ severit$

P+oto 4!" #ransverse crac6s

4!%2 ocation

Transverse crac#s may occur at isolated locations or in a lane; carriageway.

4!%! Causes

Transverse crac#ing may occur due to reflection of crac# or =oint in an underlying pavement layer.

The low temperature brittleness or o0idation of bitumen and also structural failure at concrete base

course are also causes of such crac#ing. Transverse crac#s are usually formed due to shrin#age of

bituminous mi0 on account of low temperature.

4!%" Severit$ &eve&

"everity of transverse crac#s may be defined as low, 'edium and high 9Photos 5.%.&1 a, b and c).

The low severity is assigned to *% mm wide and infre$uent crac#s medium severity is assigned to

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% mm wide. igh "everity is assigned to crac#s greater than mm wide and are fre$uent

9numerous).

4!%% #reatment

Transverse crac#s may be treated using slurry seal or rubberised bitumen.

4!3 7dge Crac6ing

4!31 S$mptoms

6dge crac#ing is defined as crac#s which develop parallel to outer edge of the pavement.

4!32 ocation

The location of edge crac#ing is normally +.% to +.( m inside of pavement edge.

9a) Fow severity 9b) 'edium severity 9c) igh severity

P+oto 4!% 7dge crac6ing

4!3! Causes

The causes of edge crac#ing are many. Fac# of lateral support from shoulder, settlement underlying

the bituminous layers, inade$uate surface drainage, shrin#age in subgrade soil, inade$uate

pavement width near curves, inferior $uality material in shoulders and thinner bituminous surface at

edge of the pavement and wet subgrade are few reasons for edge crac#ing.

4!3" Severit$ eve&

The severity levels of edge crac#s are low, medium and high9Photos 5.%.(1 a,b and c). Fow severity

is with no brea#up or loss of material, medium severity is with some brea#up and loss of

material9upto *+> of the affected length) while high severity is with considerable brea#up and loss

of material9more than *+> of the affected length).

4!3% #reatment

The following procedure; techni$ues are used for prevention or treatment of edge crac#ing.

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Promote good drainage along the edge of the road. 'a#e sure that surface water will run to

the nearby drain and not pond along the pavement edge.

Remove the dirty, poor draining shoulder material and replace it with a more permeable

material.

If truc# traffic is substantial, place a considerably thic# structural overlay on the road

surface of the order of three or four inches of hot mi0 to provide ade$uate support forheavier vehicle loads.

4!4 Ref&ection crac6ing

4!41 S$mptoms

Reflection crac#s are the sympathetic crac#s that appear in the bituminous surfacing over =oints and

underneath crac#ed pavement. The pattern may be longitudinal, transverse, diagonal or bloc#.

P+oto 4!3 Ref&ection crac6ing

4!42 ocation

Reflection crac#ing occurs most fre$uently in bituminous overlays on cement concrete pavements,

or on cement soil bases. They may also occur in overlays or surfacing on fle0ible pavements where

crac#s in the old e0isting pavement have not been properly rectified.


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4ifferential movement across the underlying crac# or =oint is responsible for development of

reflection crac#ing. /or =oint reflection crac#ing, this is movement of the cement concrete slab

beneath the bituminous surface because of the thermal and moisture changes.

4!4" Severit$ eve&s

Aot applicable

4!4% #reatment

The treatment, for all types of crac#s discussed above, would depend on whether the pavement is

structurally sound, or has become distorted or unsound. In case the pavement is structurally sound,

then the crac#s should be filled with a bituminous binder having a low viscosity so that it can be

poured and wor#ed into the crac#s. Cutbac# bitumen and emulsions are generally suitable.


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point in the direction of the traffic. /or e0ample, if bra#es are applied on a vehicle going down a

hill, the thrust of the wheels will be pointing uphill. The crac#s in this case will, therefore, point

uphill.

(a) o, () *ig+

P+oto 4"1 S&ippage of t+e ituminous ,earing coat

4"12 ocation

"lippage of bituminous surface normally occurs along the wheel path of heavy vehicles.

4"1! Causes

"lippage is caused by unusual thrust of wheels in a specific direction due to omission or

inade$uacy of tac# coat, lac# of bond between the wearing coat and the lower layer caused by a

layer of fine dust, moisture or both. /ailure of bond between two layers due to e0cessive deflection

of the pavement may also be responsible for slippage of wearing coat or successive layer.

4"1" Severit$ &eve&

"lippage may be classified as low severity and high severity slippage9Photos 5.&.* 1 a and b). Incase, slippage is at isolated locations in a lane, it is classified as low severity slippage. In case,

slippage is along the wheel path in entire lane or carriageway, it is classified as high severity

slippage.

4"1% #reatment

Rectification consists of removing the surface layer around the area affected upto the point where

good bond between the surfacing and the layer underneath e0ists and patching the area with premi0

material after a tac# coat.

4"2 Rutting

4"21 S$mptoms

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Rutting is longitudinal depression or groove in the pavement along the wheel path. Rutting is

categori-ed into three types and defined by the cause and layers in which rutting occurs, and it can

be characteri-ed by two components of the original 9initial) pavement profile change, which are

direct conse$uences of permanent deformation such as uplift and downward deformation.

(a) o, severit$ () *ig+ severit$

P+oto 4"2 Rutting in ituminous surface

4"22 ocation

Rutting generally appears along the wheel path.

4"2! Causes

The causes of rutting are the following1

9i) eavy channeli-ed traffic and overloading of a0les9ii) Inade$uate compaction of the mi0 at the surface or in the underlying bituminous courses

during construction

9iii) Improper mi0 design, lac#ing in stability to support the traffic

9iv) 7ea# pavement due to poor sub grade and inade$uate design9v) Gse of soft bitumen or wa0y bitumen

9vi) Intrusion of sub grade clay into granular base course or use of plastic filler in

3"B;7B';7''

4"2" Severit$

Rutting may be classified as low when &*+ mm deep and high severity when more than *+

mm9Photos 5.&.1 a and b).

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4"2% #reatment

The rectification consists of filling of ruts with premi0 9opengraded or densegraded) patching

materials and compacting to the desired levels. The locations of depression are first mar#ed on the

surface and then limits are determined with a string line.


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9iii) /aulty laying of surface course

9iv) Insufficient rolling;rolling a tender mi0

9v) Brea#ing action of vehicles on grade especially near intersections

4"!" Severit$

Aot applicable

4"!% #reatment

If the surface is thin, the same is scarifiedH including some portions of the underlying base, and the

scarified material is recompacted. < new surfacing layer is then laid. Cutting of high spots with a

blade with or without heating and addition of leveling course materials can also be resorted to.

"preading of sand bituminous premi0 with a drag spreader with its blade ad=usted to =ust clear the

high spots can also be an effective way to ma#e up the corrugation. The area is then thoroughly

rolled.

4"" S+oving

4""1 S$mptoms

"hoving is a form of plastic movement within the bituminous layers resulting in bulging of the

pavement surface. Photo 5.&.& shown shoving of bituminous layers.

P+oto 4"" S+oving of ituminous surface

4""2 ocation

"hoving occurs characteristically at points, where traffic starts and stops 9intersections, busstops),

on hills roads or where vehicles accelerate or bra#e on grades and on sharp curves. The first

indication of shoving appears in the form of slippage crac#s which are crescent shaped crac#s, with

the ape0 of the crac# pointing in the direction of the shove. Photo 5.&.*& shows shoving of

bituminous layers. "hoving occur near the wheel path.

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4""! Causes

9i) Fac# of stability in the mi0 9e0cessive binder, high proportion of fines, soft binder) in

the bituminous surface or base course.9ii) Fac# of bond between bituminous surface and underlying layer

9iii) eavy traffic movement involving negotiation of curves and gradients

4""" Severit$ &eve&

Aot applicable

4"8"% #reatment

The rectification consists of removing the material in the affected area down to a firm base and

laying a stable premi0 patch.

4"% S+a&&o, depression

4"%1 S$mptoms

"hallow depressions are isolated low areas of limited si-e, dipping about ( mm or more below the

profile, where water will normally become stagnant. The shallow depressions may or may not be

eventually accompanied by crac#ing of surface. These may also lead to further deterioration of the

surface and cause discomfort and unsafe surface to traffic. < view of shallow depression in shown

in Photo 5.&.(

P+oto 4"% S+a&&o, depression in ituminous surface

4"%2 ocation

"hallow depressions are generally restricted to wheel path; heavy traffic lanes.

4"%! Causes

"hallow depressions are caused by isolated settlement of lower pavement layers due to poc#ets of

inade$uately compacted sub grade or subse$uent pavement layers.

4"%" Severit$ &eve&

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Aot applicable

4"%% #reatment

"hallow depressions are made up by filling with premi0 materials, open graded or dense graded,

and compacting to the desired profile as the surrounding pavement.

4"3 Sett&ements and up+eava&

4"31 S$mptoms

"ettlements and upheavals are characteri-ed by relatively large deformations of the pavement

compared to shallow depressions. These are dangerous to traffic and cause reduction in speed of

traffic. These are generally followed by e0tensive crac#s over the pavement surface in the affected

region. "ettlements and upheavals are shown in Photo 5.&. and 5.&.5, respectively

P+oto 4"3 Sett&ement in ituminous surfacing

P+oto 4"4 /p+eava& in ituminous surfacing

4"32 ocation

"ettlement may be along the wheel path or at isolated locations in a lane carriageway.

4"3! Causes

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The following are the causes for settlements and upheavals in bituminous pavements1

9i) Inade$uate compaction of the fill at locations behind bridge abatements, over utility cuts,

etc.

9ii) 60cessive moisture in subgrade and permeable layer of subbase and base caused by

capillary action or poor drainage.

9iii) Inade$uate pavement thic#ness.

4"3" Severit$

Aot


30/77

4%12 ocation: "tripping is either locali-ed or e0tended to lane or entire carriageway.

4%1! Causes

"tripping may be caused by the following reason1

9i) Gse of hydrophilic aggregates.9ii) Inade$uate mi0 composition.

9iii) Continuous contact of water with the coated aggregate.

9iv) Initial over heating of the binder or the aggregate or both.9v) Presence of dust or moisture on aggregate surface when it comes in contact with the

bitumen.

9vi) ccurrence of raining or dust storm immediately after the construction

9vii) igher concentration of salt in soil and raining water9viii) Gse of improper grade of bitumen

9i0)


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4%22 ocation

Raveling may occur on any part of a lane or carriageway.

4%2! Causes

Raveling is li#ely to occur on a surface due to one or more of following reasons.

(i) Inade$uate bitumen content in a mi0

(ii) verheating of bitumen during mi0ing process

(iii) Inade$uate compaction during construction

(iv) "tripping of bitumen from aggregate due to water at interface

(v) Construction during cold and wet weather

(vi) Gse of inferior $uality aggregate prone to fracture, crushing and opening of new faces.

(vii) Gse of absorptive aggregates

(viii) 60cessive ageing of binder

(i) Fac# of performance related contract specifications

() Improper filler ; bitumen ratio(i) igh intensity hydrostatic pressure due to combined effects of traffic and water.

(ii) 4evelopment of inclement weather 9moisture, free-ing) immediately after construction.

(iii) Traffic stresses e0ceed brea#ing strength of mi0

4%2" Severit$ &eve&

Raveling may be classified to three severity levels, vi-.,low severity, medium severity and high

severity9Photos 5.(..1 a, b and c). Fow severity is when some loss of fines is associated with initial

stage of binder wearing out, medium is when loose particles e0ists with some loss having binder

wearing out to a rough surface and high severity is when surface is too rough with loss of

aggregates.

9a) Fow severity 9b) 'edium severity 9c) igh severity

P+oto 4%2.ie, of Rave&ing

4%2% #reatment

The treatment of Ravellled surface shall depend upon severity of Raveling.

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9a).Fow severity Raveling1 The low severity Raveling may be corrected by application of fog

seal, sand seal or seal coat, slurry seal and microsurfacing9b).'edium severity Raveling1 This may be corrected by application of seal coat slurry seal or

microsurfacing treatment in affected area

9c). igh severity Raveling1 4epending upon condition of Ravellled surface and specification of

e0isting surface. The high severity Raveling may be corrected by single or multiple

applications of li$uid seal coat, slurry seal, microsurfacing and surfacing of thin overlay of

appropriate mi0 specification li#e mi0 seal surfacing or open graded premi0 carpet.

4%! Pot+o&es

4%!1 S$mptoms

Pot holes are bowl shaped cavities of varying si-es in a bituminous surface or e0tending into the

binder; base course, caused by locali-ed disintegration of material.

9a) "mall 9b) 'edium 9c) Farge

P+oto 4%! Pot+o&es of different severit$

4%!2 ocation

Potholes may occur in any part of road surface.

4%!! Causes of pot+o&es

The most common cause of pothole formation is loss of adhesion in bituminous wearing coat due to

the ingress of water into the pavement or due to higher voids in surface. The pavement gets softened

as a result of loss of cohesion, and under the action of traffic. The formation of pothole is

aggravated due to use of plastic filler in granular base. If not attended timely and properly,

aggregates in the surface get progressively loosened to result in a pothole. Fac# of proper bond

between the bituminous surfacing and the underlying water bound 'acadam base layer can alsocause formation of potholes. Insufficient bitumen content in locali-ed areas of the surfacing layer

can also cause formation of potholes. < thin bituminous surface, which is unable to withstand the

heavy traffic, can also cause formation of potholes, when associated with improper or inade$uate

camber. In densegraded mi0tures, potholes can be caused by too much fines or too few fines.

4%!" Severit$

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Potholes may be classified as small, medium and large9Photos 5.(.% 1 a, b and c). < small pothole is

defined as 2% mmdeepand 299mmwide. The medium pothole is defined as ( to (+ mm deep and

%99 mmwide. The large potholes are those greater than (+ mm deep and (++ mm width

4%!% #reatment

The rectification consists of filling potholes with open graded or dense graded premi0. Potholes

can be repaired by various methods

*. 'i0es 9cold mi0ed; hot mi0ed) for immediate use. "torable cold mi0es 9cutbac# IRC1** ; emulsion Based IRC1*++)

%. Readymade mi0es

&. Cold mi0es by Patching machines

4%" 7dge Brea6ing

4%"1 S$mptoms

< common defect in bituminous surface is edge brea#ing wherein the edge of the bituminous

surface gets bro#en in an irregular way. Photo 5.(.& shows this type of defect. In case distress in

not attended in time, the surfacing may peel off in chun#s at the edges.

P+oto 4%" 7dge Brea6up

4%"2 ocation

4istress is restricted to edges upto %+ cm from edge.

4%"! Causes

The following are the causes for edge brea#ing

Infiltration of water which ma#e the foundation layers wea# causing the pavement edges

to brea#

7orn out shoulders resulting in insufficient side support to the pavement.

Inade$uate strength at the edge of the pavement due to inade$uate compaction.

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Fower layer of pavement being wider than upper layers.

Too narrow width

4%"" Severit$

Aot applicable

4%"3 #reatment

The shoulder and the pavement materials in the affected area should be entirely removed to a

regular section with vertical sides. The pavement and the shoulders should be built up

simultaneously with thorough compaction. < bituminous surface similar to that in the ad=acent

reach should be laid. The shoulder should have ade$uate slope to drain away to water. < slope one

per cent steeper than the camber of the bituminous surface should be found generally necessary for

earthen shoulders. In order to prevent the edges from getting bro#en again, the maintenance

operations should include periodic inspection of the shoulder condition and replacement of worn

out shoulder material with ade$uate compaction. In sandy areas where the soil is li#ely to be eroded

by wind and rain, it may be advantageous to have bric# paving at least for some width to protect the

edges. "urface and subsurface drainage, wherever deficient, should be improved

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Section 8

Preventive maintenance

81 Introduction

4elays in maintenance increase the severity of distress in pavement leading to higher maintenance

e0penditure. Preventive maintenance is a planned maintenance activity, which decreases rate of

surface deterioration and e0tend service life of bituminous pavement. It is a maintenance activity as

a planned strategy of cost effective treatment of e0isting roads and its appurtenances that preserves

the system, prevents future deterioration and improves the functional condition of the system

without contribution to load carrying capacity of pavement. "uch treatments are cost effective, if

provided on a pavement in fair to good condition. The placement of right preventive maintenance

treatment at the right time saves pavement from leading to poor condition 9Table (.* to (.%), where

rehabilitation and reconstruction would be inevitable

82 Se&ection of preventive maintenance treatment

Preventive maintenance treatments shall be selected based upon the condition of e0isting pavement.

The crac#ing, rutting, riding $uality, climate and traffic are given due consideration in selection of

preventive maintenance treatments. The concept of preventive maintenance stipulates that

deterioration modes can be anticipated and at least partially mitigated before their occurrence. This

provides following long term solutions.

Improved level of service resulting from improved pavement performance

4elayed need for rehabilitation and reconstruction

Fife cycle cost saving

/or preventive maintenance applications, the following guidelines must be considered

60isting distress to be treated


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Timing of treatment for best results

'a0imi-ing performance while minimi-ing cost

< thin overlay may not be considered as a preventive maintenance, when it is applied to a distressed

pavement in poor condition. "lurry seal; microsurfacing may not be considered as preventive

maintenance, when placed on a e0tensively crac#ed surface. < preventive maintenance strategy

comprises following

Identification of causes of distress

'easurement of distress

"election of appropriate treatment

Timing of treatment

/igure 2.* illustrate timing of preventive maintenance treatment, while selection of treatment

depends upon type of distress causes, severity, climate and traffic. Refer to Tables (.* to (.( in

section ( of document and conceptual illustration given in /igure 2.*, preventive maintenance shall

be under ta#en when drop in $uality of pavement surface is less than %+ > a $uantified in Tables (.*

36 | P a g e


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to (.% by pavement condition rating criteria. Preventive maintenance treatments shall be effective

before the pavement condition ratting drops below . The type of treatment shall depend upon

pavement condition ratting as well as type and area of distress. The detailed warrants for choice of

the treatment are given in Tables 2.* to 2.5.

"uitable preventive maintenance treatment may be identified by following attributes.

Propose of treatment


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The description and warrants for preventive maintenance treatments are given in Table 2.* to 2.5

#a&e 81 Crac6 fi&&ing or crac6 sea&ing

Crac6 Fi&&ing orCrac6 Sea&ing ;arrant

C&imate #raffic 'ddressed imitationsThese treatments are intended

primarily to prevent the intrusion

of moisture through e0isting

crac#s. Crac# sealing refers to a

sealing operation that addresses

wor#ing! crac#s, i.e., those that

open and close with changes in

temperature. It typically implies

high $uality materials and good

preparation. Crac# filling is for

crac#s that undergo little

movement. "ealants used are

typically elastomers modified

bituminous materials that soften

upon heating and harden uponcooling.

Treatment

can perform

well in all

climatic

conditions.

Performance

is not

significantly

affected by

varying

traffic.

J Fongitudinal

crac#ing

J 'inor bloc#

crac#ing

J Transverse

crac#ing

JAo structural

benefits,

J


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#a&e 82 Fog Sea&

escription ;arrants

C&imate #raffic Conditions 'ddressed imitation

/og seals are placed

primarily to seal the

pavement, inhibit

Raveling re=uvenate

hardened; o0idi-ed

bitumen surface, and

provide some

pavement edge

shoulder delineation.

/og seals are very

light applications of

a diluted bitumen

emulsion placed

directly on the

pavement surface

with no aggregate.

Typical applicationrates range from

+.% to +.&( :g. per

m

Treatment

performs well

in all climatic

conditions.

Increased

traffic can

increase

surface

wear,

Fongitudinal,

transverse, and bloc#

crac#ing Raveling;weathering

9loose material must

be removed) Bitumen aging,

o0idation and

hardening Ao structural

improvement, but can

help reduce moisture

infiltration through

fatigue crac#s 9if their

severity is low)

J "tructural

failure 9such

as significant

fatigue

crac#ing)

J /riction loss

JThermal

crac#ing

"ite Restrictions Aot appropriate for surfaces with poor s#id resistance, as it will lower the

s#id resistance further.

Construction

Considerations

Typically, a slowsetting emulsion is used which re$uires time to brea#,!

the pavement is sometimes closed for

hours for curing before being reopened to traffic.

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#a&e 8! S&urr$ sea&

C+aracteristics ;arrants


< mi0ture of wellgraded

aggregate 9fine sand and

mineral filler) and

Bitumen emulsion that is

spread

over the entire pavement

surface with either a

s$ueegee or spreader bo0

attached to the bac# of a

truc#. It is effective in

sealing lowseverity

surface crac#s,

waterproofing the

pavement surface, and

improving s#id resistance

at speeds below + :m;h

9%+ mph). Thic#ness is

generally less than *+mm

Treatment

performs

effectively in

all climatic

conditions.

Performanc

e in terms of

surface

wear is

affected by

increasing

traffic.


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C+aracteristics ;arrants


'icrosurfacing

consists of a mi0ture

of polymermodified

emulsified asphalt,

mineral aggregate,

mineral filler, water,

and additives applied

in a process similar to

slurry seals. Gsed

primarily to inhibit

Raveling and

o0idation of the

pavement surface.


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'ddressed

Bitumen emulsion is

applied directly to the

pavement surface 9*.(K to

.5

F;m) followed by theapplication of

aggregate chips 92 to 5

#g;mwhich are then

immediately rolled to imbed

chips 9(+ to 5+ percent).


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combinations of

asphalt cement and

aggregate applied to

the pavement in

Thic#nesses between

about *( and ( mm

4ensegraded,

opengraded,

premi0 and stone

matri0 mi0es are

used

performs well

in all climatic

conditions.

not be affected by

different traffic

condition

Thin overlays are

not structural layers

and as such should

not be sub=ected to

strain from

loadings. "uch

layers may be

sub=ect to topdown

crac#ing undercertain

combinations of

loadings,

environmental

conditions, and

pavement

structures.

J Fongitudinal and

transverse

crac#ing

J Raveling;weathering

9loose

surface material must

be

removed)

J /riction loss

J Roughness

J Bleeding

J Bloc# crac#ing may

perform better withadditional milling)

Structura&

Rutting 9assumes

rutting has

stoppedH re$uires use of

separate rutfill

application)

failure 9i.e.,

fatigue

crac#ing)

J 60tensive

pavement

deterioration,

little

remaining life

J Thermal

crac#ing

"ite Restrictions 6dgeshoulder dropoff should be considered. "urface should be uniform to

ensure uniform compaction.

Construction

Considerations

"urface must be clean. < tac# coat prior to overlay placement will help improve

the bond to the e0isting surface. Thin '< overlays dissipate heat rapidly and,

therefore, depend upon minimum specified mi0 placement temperatures and

timely compaction..

#a&e 84 /&trat+in Friction Courses

escription ;arrants


Relatively new

treatment and

consists

Treatment

should

perform

Capable of

withstandin

g high


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of a gapgraded,

polymer modified

*+ to + mm layer

placed on a tac# coat

formed by the

application of a

heavy, polymer

modified bitumen

emulsion. Treatment

effectively addresses

minor surface

distresses and

increases surfacefriction.

well in all

climatic

conditions

volumes

and truc#

traffic better

than other

thin

treatments.

addressed with cold

milling.

JRaveling;weathering

9loose surface material

must be removed)

J /riction loss

J Roughness

J Bleeding

J Provides some

increased capacity and

retards fatigue crac#ing.

Aot suited for rutted

pavements.

fatigue

crac#ing

and;or deep

rutting)

J 60tensive

pavement

deterioration,

little

remaining life

J Thermal

crac#ing

"ite Restrictions Gltrathin overlays should only be placed on structurally sound

pavements. Focali-ed structural problems should be repaired prior to

overlay application.

Construction

Considerations

Re$uires special paving e$uipment to place the mi0.

Section >

Periodic Rene,a&s

>1 0eed and importance of periodic rene,a&s

Periodic renewals consist of the provision of a surfacing layer at regular intervals of time or at a

specified condition, so as to preserve the re$uired serviceability level of the pavement surface and

44 | P a g e


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offset the wear and tear caused by traffic and, weathering. Periodic renewals represent the

maintenance, which is needed to prevent deterioration of the pavement and to ensure that initial

$ualities are #ept up for the future re$uirements of traffic during the design life of the pavement.

6arly detection and repair of noticeable distress; defects can prevent a ma=or damage of the surface.

>2 P&anning and programming of rene,a&s

The general practice in the country is to finali-e renewal programme on an annual basis. The

renewal programme for each section of a road should be decided well in advance. nce the

programme is finali-ed, steps could be ta#en to secure the re$uired allocations and start the

preliminary field action such as mobili-ation of resources. 7hile the nomenclature Periodic

Renewal! would imply to the renewal treatment be carried out at a fi0ed and pre decided fre$uency,

it would neither be practicable nor desirable to follow implicitly of any specified fre$uency

irrespective of the condition of the road surface proposed to be renewed. The most effective way toplan a renewal programme is to carry out periodic inspections of the road surface at suitable

intervals in order to assess its condition and needs for providing renewal treatment. 8isual

inspection and actual measurements, if re$uired"!ppendix 1 and 2#of the roads as detailed in

"ection ( should be carried out manually or automated machine 9!ppendix 3). In addition, special

inspections are also necessary before and after the rains so as to assess the need for pothole repair

and patching and other remedial measures re$uired to be carried out either in advance or together

with the renewal treatment.

>! Identification of &engt+ to e rene,ed

The lengths of the road showing signs of distress such as hungry surface;hairline crac#ing,

Raveling etc., should invariably be included in the renewal programme. This would ensure that the

surface of the road and the pavement structure do not deteriorate further. The lengths of the road

which would be due for periodic renewal on the basis of the pavement condition inde0 and

periodicity should be inspected closely and decision whether to include these in the renewal

programme or to postpone the renewal for a specified period should be ta#en depending upon the

condition of the road surface. In cases, the nature of distress;failure seen on the road is severe and

of considerable e0tent and the causes are deepseated and where it is considered the pavement

cannot be improved with renewal treatment, detailed investigations shall be carried out and special

measures shall be ta#en for correcting the same.

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>" #$pes of rene,a& treatments

The types of bituminous surfaces those can be adopted are surface dressing 9one or two coats), thin

premi0 carpet, mi0ed seal, stone matri0 asphalt , hot;cold mi0 semi dense and dense bituminous

concrete. 'icrosurfacing in one layer or two layers can also be used for renewals. These surface

have different life spans depending upon traffic and environmental conditions.

The specifications adopted for the renewal layer on a particular road would depend upon the type of

the original surface and its condition at the time of renewal. /ollowing standards;specifications may

be referred for periodic renewals

9i) IRC 1 *& LRecommended Practice for pen 3raded Premi0 CarpetD

9ii) IRC 1 **+ L"tandard specifications and Code of Practice for 4esign and Construction of

"urface 4ressingD

9iii) IRC 1 *** L"pecifications for 4ense 3raded Bituminous 'i0esD

9iv) IRC 1 "P 52 L"pecifications for 'i0 "eal "urfacing9'""), Close 3raded Premi0"urfacings9C3P")

9v) IRC 1 "P 5K LTentative "pecifications for "tone 'atri0 % Periodicit$ of rene,a&

Based on the e0perience and condition indices given in Table (.* to (.(, broad guidelines for the

type of renewals are given in Table K.*. This may be utili-ed as a guide for wor#ing out annual

renewal programme on different sections of roads.

#a&e >1 Suggested Rene,a& #reatment on F&ei&e Pavement

Road

Categor$

Condition

Rating?

Roug+ness5

mm=6m

Suggested #reatment??

(#+ic6ness5 mm)

A &++ %+&+ BC

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" 2++ %+ BC;%+ "4BC

'4R; RR * &+++ "4;PC;'"";"4BC

9+()

Grban Road ++ %+&+ BC;"4BC; Coat 'icro

"urfacing

? 7hen the condition of road is rated as *, it is recommended that a detailed investigation is

carried out to assess the strengthening re$uirement, if any. In case, the pavement is found to be

structurally ade$uate, then the periodic renewal will suffice.

MM 7herever feasible, recycling of wearing course may be preferred

The priority of renewal treatment may be decided based on rating assigned as e0plained in section

(.*, earlier. If there are *+ roads9say), with ratings from *.& to *.2, the roads may be arranged based

on the ascending order of condition rating and the periodic renewal shall be prioritised in the same

order sub=ect to budgetary allocations.

>3 Rectification of profi&e at t+e time of rene,a&

The camber and super elevation provided initially on a road tend to get flattened out due to traffic.

Before the renewal of surface is done, the cross profile should be corrected by means of a suitable

profile correction course;leveling course, which may be compatible with e0isting surface

specification.

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Section 19Materia&s and Met+ods for Rectification of istress on Bituminous Surface

191 enera&

The section 5 has dealt with the identification of the distress, measurement of distressed area, types of

defect and their causes, and the maintenance measures to be ta#en up in each case. This section describes

various materials re$uired for maintenance methods, which are applicable to Routine, Preventive and

Periodic 'aintenance!. Routine maintenance is covered in section 5. Preventive type of maintenance

activities are covered in section 2. 'aintenance operations of periodic nature are described in section K.

Therefore repair materials and methods discussed in this section fall under three categories1 9i)

Re=uvenation 9ii) "eal and 9iii) Patching, Re=uvenation of o0idi-ed and hungry bituminous surface can

be done by application of li$uid bituminous materials. The seal coat is a thin application of bitumen,

which shall be covered with fine aggregate; sand. "eal coat may be premi0ed material or a spray

application. Patching is an application of premi0ed bituminous mi0ture. Patching is done to fill pot

holes, correct shallow depressions, rutting and correct edge irregularities. The details of materials and

methods are discussed below1

192 Bituminous Materia&s

1921 Paving Bitumen

Paving Bitumen conforming to I"1 5%1+* is recommended for road maintenance wor#s, unless

otherwise specified. Paving bitumen is classified in four grades based on viscosity, vi-., 83*+, 83

+, 83%+ and 83&+.

1922 Cutac6 itumen

Cutbac# bitumen of different grades are re$uired for cold weather construction as well as maintenance

under allweather conditions. 'edium curing cutbac# bitumen 'C2++ conforming I"1 *5 is

recommended for preparation of storable bituminous pothole; patching mi0.

192! Bitumen emu&sion

Bitumen emulsion is a twophase system consisting of bitumen, water and one or more additives to

assist in formation and stabili-ation and to modify the properties of the emulsion. The bitumen is

dispersed throughout the water phase in the form of discrete globules, typically *.+ to ( Nm in diameter,

which are held in suspension by electrostatic charges stabili-ed by an emulsifier. Bitumen emulsions

conforming to I"1 2225 are recommended for various maintenance applications including preparation of

cold mi0es and patching mi0es.

48 | P a g e


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192" Foam itumen

/oaming of bitumen is a means of reducing the binder viscosity and increasing the binder volume. /oam

bitumen is produced in an e0pansion chamber in which cold water at a level between * and ( > by

weight of bitumen is in=ected under pressure into hot bitumen to produce foam. 60pansion ratio and half

life are two important properties of foam bitumen. The e0pansion ratio is defined as the ratio of thevolume of foam produced to the volume of li$uid bitumen in=ected. The life time of foam is e0pressed as

the Lhalflife, defined as the time after which the ma0imum volume of foam is reduced by a factor of

two. It is measured in seconds. The foam bitumen is used for stabili-ation of recycled asphalt pavement.

192% Modified itumen

'odified bitumen is the binder whose properties have been modified by the use of polymers and

rubbers. IRC 1 "P (% and I"1 *(& specify different grades of modified bitumen for construction and

maintenance of bituminous roads.

1923 Modified emu&sions

'odified emulsions are defined as bitumen emulsions whose a$ueous phase is generally modified by

late0 of the rubber. "ometimes, bitumen is also modified before emulsification. These emulsions are

used for microsurfacing applications. The specification of modified emulsion for microsurfacing is given

in IRC1 "P1 2*.

1924 Re@uvenating agents= sea&ants

Re=uvenating agents are used for restoration of physico chemical properties of o0idi-ed bitumen of dry

and hungry surface or o0idi-ed bitumen in recycled asphalt pavement. "ometimes, these re=uvenating

agents are used as sealants. The viscosity value of these re=uvenating agents lies between *++%++

seconds at + C by "ay bolt fural viscometer.

1928 'ntistripping agents

;arm mi additives

< warm mi0 asphalt technology utili-es chemical additives that have little effect on rheological

properties of the binder. These additives reduce mi0ing, laying and compaction temperature of

bituminous mi0es. The guidelines for warm mi0 asphalt are given in IRC1 "P1 *+*.

49 | P a g e


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19! Maintenance tec+niAues

19!1 Re@uvenating Sea&

Re=uvenating seals are applications of thin layer of li$uid bituminous material such as low viscosity

grade bitumen li#e 83*+, cutbac# bitumen, bitumen emulsion or bituminous sealants 9Re=uvenating


51/77

no--le or a pressure distributor. Cover aggregates are then spread at the specified rate and rolled in

position with suitable steel wheel roller. 7hen viscosity grade bitumen is used, the road can be opened

to traffic on the following day or if re$uired to be opened immediately with a speed restriction of *+

#m;h shall be enforced till the following day. 7hen cutbac# bitumen is used, the finished surface shall

be closed to traffic until it has sufficiently cured to hold the cover aggregate in position. If emulsion is

used, the road can be opened to traffic after % hours.

19!2 Fog Sea&

/og seal is defined as a light application of dilute 9"" or tailor made) bitumen emulsion which is used

primarily to seal an e0isting bitumen surface to reduce Raveling and enrich dry and weathered surfaces.

/og seal is a method of incorporation of bituminous binder to an e0isting pavement to improve its

waterproofing characteristics, prevent further stone loss by holding aggregate in place, re=uvenating

surface and improving the surface appearance. owever, its inappropriate use can result in a slic#

pavement. 4uring application, bitumen emulsion wets the surface of the aggregate. Cationic emulsion

can displace water from the surface of aggregate and e0isting binder film. The rate of brea#ing emulsion

is dependent on several factors including weather conditions 9e. g. wind, rain, temperature, etc.).

Re=uvenating emulsion has oils which help in softening of the o0idi-ed binder in e0isting surface, thus

reducing its viscosity. This also improves the fle0ibility of the binder, which reduces the possibility of

cohesive failure. This may be beneficial in situations where the surface has an open te0ture and the

e0isting binder has become hard and brittle due to aging.


52/77

preventive and corrective maintenance needs. This treatment does not increase the structural strength of

a pavement. < pavement which is structurally wea#, should be repaired first before applying slurry seal.

Ruts, humps, distressed pavement edges, crown deficiencies, or other surface irregularities that affect

riding $uality should be corrected before placing slurry seal, which is considered to be a very effective

maintenance techni$ue for the surfaces of older pavements. It will fill the surface crac#s, stop Raveling

and loss of matri0, improve s#id resistance, generally protect the pavement, reduce water and o0idative

deterioration, and finally e0tend the overall pavement service life. "lurry seal has the following ma=or

advantages1

Rapid application and early open to traffic

60cellent surface te0ture and friction resistance


53/77

spread over a properly prepared surface. The finally laid microsurfacing shall have a homogeneous mat,

adhere firmly to the prepared surface and provide friction resistant surface te0ture throughout its service

life. The mi0 is to be a $uic# setting system i.e. it should be able to receive traffic after * hours

depending upon weather conditions. This may be used for a variety of purposes such as surface sealing

treatment to improve s#id resistance, and longevity; of surfacing, durability and to seal fine and medium

crac#s. It is applied on an e0isting pavement surface which is structurally ade$uate but is showing the

signs of distress such as premature aging, aggregate loss, crac#ing, high degree of polishing etc.

3enerally, microsurfacing is laid in single layer, but when the e0isting surface is highly polished and; or

crac#ed, it is advisable to apply it in two or more layers.


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#a&e 192: ifferent #$pes and Specifications for Microsurfacing

Items #$pe II #$pe III


55/77

"and bitumen premi0 patching consists of laying a mi0ture of fine aggregate and bituminous binder to

rectify crac#s, slippage, corrugations, shoving, shallow depressions and Raveling. The fine aggregate

shall be a medium coarse sand 9fineness modulus of more than .( ) or fine grit passing *.5+ mm I"

"ieve and retained on *2+micron I" "ieve. The binder can be paving viscosity based bitumen or rapid

curing cut O bac# such as RC%, or a medium curing cutbac# such as 'C%. The area is thoroughly

cleaned and a tac# coat with bitumen emulsion or 83*+ bitumen or cutbac# 9RC% or 'C%) is applied

at the rate of .( #g per *+.s$.m. The mi0 is prepared in suitable mechanical or handoperated mi0ers by

mi0ing binder and sand. The $uantity of sand and binder shall be +.+ cu.m. and .2 #g 9$uantity of

binder in terms of penetration grade bitumen) per *+ s$.m. area respectively. The mi0 is spread and laid

wherever re$uired. 7hen smoothening a corrugated surface , it may be e0pedient to use a drag spreader

with its blade ad=usted to clear the high sports. The mi0ture is then rolled thoroughly till it is compacted.

19!4 -pen D graded Premi Patc+ing

pen O graded premi0 patching consists of ma#ing up the area to be patched by a premi0 open O graded

material consisting of a binder and aggregates, compacting and finishing with a seal coat. This repair

method is applicable for fatty surfaces, slippage, rutting, shoving shallow depressions and pot holes.

The binder can be bitumen of suitable viscosity grade, rapid curing cutbac# such as RC% or medium ;

slow setting or tailormade bitumen emulsion. The details of materials and construction procedure are

given in IRC1*& and IRC1 "P1 *++

19!8Maintenance Mitures

'aintenance mi0es are classified in four types1

9a).'i0es for Immediate Gse

9b)."torable 'i0es

9c). 'aintenance mi0es using R


56/77

Sieve Sie Percent Passing

K.( *++

&.5( &+*++

.% *+&+

*.*2 +*+

+.+5( +

The $uantity of emulsion shall be 5 to 2 > by 9&.( to (.( > residual bitumen) weight of aggregate.

() Stora&e Maintenance Mies

4uring the cold weather and rainy months, most of the maintenance mi0es used are those which may be

stored ; stoc#piled, which can be produced in late summer or early months of winter, transported and

stored in remote locations for later use. "uch mi0es are usable for periods up to si0 months and are

wor#able without the use of heat. These must be covered by polythene or tarpoline. The production of

stoc#pile maintenance mi0 is simple and includes a pug mill type mi0er. "low setting 9"") grade or

tailor made emulsion is to be used for this purpose. The aggregate gradation for stoc#pile mi0es is same

as given in Table *+.&. The duly mi0ed material shall be stored in a clean, covered area to prevent

contamination and not stored in a low area or depression where water could get into the mi0. /or

prolonged stoc#piling and to be usable at lower temperatures, a high float medium setting emulsion is

recommended. These mi0es may contain residual bitumen in the range of &.( to (.(> depending on

gradation and surface characteristics of aggregates.

(c)Maintenance Mies using R'P (MMR'P)

'any bituminous pavement overlay pro=ects include cold milling of bituminous surface and produce

large $uantities of Reclaimed


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Ready to use cold mi0 patching materials are also effective for instant repair of potholes on roads under

inclement weather and operating conditions. These mi0es are e0pected to contain &.( to (.(> of residual

bitumen and continuously graded aggregates. "uch mi0es can be stored upto si0 months from date of

manufacture. 'ore details are given in "pecification for Readymade Bituminous Pothole Patching 'i0

Gsing Cutbac# Bitumen 9IRC1 **) and IRC1 "P1 *+++*.

The following tests shall be carried out for assessment of the $uality of maintenance mi0es.

Binder content

7et coating test

"tatic Immersion test

7ater resistance test

7or#ability test

Bond test

4etails of test are given in IRC1 "P1 *++ and IRC1 **

Pothole shall be cleaned of loose material and dust with a stiff wire brush. Pothole need not be dry.

owever, e0cess water, if any in the pothole, shall be removed from the pothole. < prime coat shall be

applied to 7'';granular surface before placing the mi0 to ensure good bond at the bottom. The mi0 is

intended for filling potholes up to 5( mm deep. /or deeper potholes 9more than 5( mm), patching mi0

shall be placed and compacted in or more layers of ( to 5( mm. Initially the pothole may be filled

using crusher run macadam 9CR'). /irst the outside edge or periphery of the patch shall be compacted

with a hand rammer and then compaction shall proceed inwards. To prevent initial pic# up of the loose

mi0 by the hand rammer either continue to wet the hand rammer with water or place empty plastic lined

bags on the loose mi0. /or deep potholes, place the patching mi0 and compact in 5( mm thic# layers.

Stress 'soring Memrane for Crac6 Sea&ing

This method deals with sealing of the crac#s using a "tress


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#a&e 19%: uantit$ of Materia&s ReAuired for 19 sAm of Road Surface for Stress 'soring

Memranes

S&

0o

#$pe and ;idt+ of

Crac6

Specification of

S'M to e app&ied

uantit$

of inder

6g=19m2

uantit$ of c+ipping

*. air crac#s and map

crac#s upto %mm

width

"ingle coat "


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Section 11

#oo&s and 7Auipments

111enera&

Gse of mechani-ed methods and techni$ues for carrying out various maintenance activities are

recommended for achieving efficiency and $uality in maintenance operations. "uitable tools, plants and

e$uipment of appropriate capacity need to be deployed #eeping in view the type and magnitude of the

wor# and desired output. Proper maintenance and up#eep of all maintenance tools, plants and e$uipment

is very important to ensure $uality wor#. It is always advisable to follow e$uipment maintenance

instructions and schedule as per manufacturerDs specifications. "ome of the tools and e$uipment

especially tend to develop inaccuracies and defects with usage and hence, their regular

monitoring;chec#ing and rectification is essential.

Crac# filling, pothole filling and patching wor#s form the ma=or part of the bituminous surface

maintenance. 7hile the crac# sealing is generally carried out by manual methods, pothole filling and

patching can be efficiently carried out by mechani-ed methods. .

112 Pot+o&e Fi&&ing=Patc+ing

There are two main elements of durable pothole filling;patchingH the material and the repairs process.

/or every combination of these two factors, the cost effectiveness of the overall pothole filling ;patching

wor# will depend on material, labour and e$uipment costs and the $uantity of the wor#. The most

economical combination of materials and process to the e0tent possible should be adopted to produce

long lasting and cost effective patch repairs.

11! #oo&s and 7Auipment for Pot+o&e=Patc+ Repairs

/or carrying out durable, long lasting and cost effective repairs of potholes and patches, the following

tools and e$uipment are generally re$uired1

i) 'aterial truc#9with hand tools)

ii) 6$uipment truc#

iii) 'echanical tool;e$uipment for pavement cutting E dressing

iv) Compaction device 9vibratory wal# behind roller or plate compactor)

v)


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11" Modern Moi&e Mec+anised Pot+o&e Fi&&ing=Road patc+ing #ec+no&ogies

/or the durable and cost effective pothole filling;road patching, innovative indigenous and imported

mechani-ed road patching technologies are available. 'ost machines and techni$ues incorporate use of

cold mi0es, while some use infrared radiation techni$ue for heating the road surface for use as patching

material. The following are some of the widely used technologies for the purpose.

'achine 'i0ed "pot Cold 'i0 and Patching 6$uipment

'obile 'echani-ed 'aintenance Gnits

et patching 8elocity "pray In=ection Technology

The deteriorated portion of the e0isting pavement ad=oining the pothole should be cut and loose particles

removed before patching of pothole. ' vie, of various mac+ines is given in P+otos 111 to 11"

111 Production of 7mu&sified Co&d Mi for Patc+ing Mies

112 .e&ocit$ In@ection Eetpatc+ing Mac+ine

60 | P a g e


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11! Infrared road patc+ing tec+no&og$

11" Moi&e Mec+anised Maintenance /nit

These e$uipment and technologies are for general applications for pothole filling; patch repairs.

'obile mechani-ed maintenance units may be e$uipped for other applications also. /or more specific

applications or other maintenance treatments, various e$uipment and methods that are generally used

are detailed in documents listed in previous "ection K.&.

61 | P a g e


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Section 12

'rrangements for #raffic and Safet$ Measures during Road Maintenance

121The road construction and maintenance activities are the integral part of road networ# development

and its preservation. 'aintenance of roads is a normal recurring and periodic activity. 4uring carrying

out maintenance activities, proper arrangements for safe operation and movement of normal traffic,

maintenance wor#ers and e$uipment in the wor# -ones are most important. The road wor# -ones are

areas of conflict between normal operating traffic, wor#ers, maintenance e$uipment and machines and

wor# -one traffic. Care has to be ta#en to avoid; remove conflicts between wor#ers, maintenance

e$uipment and traffic.


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4esign, placement, operation, maintenance, and uniformity are aspects that should be carefully

considered in order to ma0imi-e the ability of a road sign to meet these basic re$uirements.

12"The maintenance related activities shall confine to half of the pavement width at a time leaving the

other half for use by the traffic, to the e0tent possible. therwise, diversion roads may have to be

constructed or the traffic diverted to some other alternative route with a proper information arrangement

about the alternative. The maintenance operation itself can be conveniently confined to a small length at

a time. The appropriate warning sign to be used such as 'en at 7or#! sign during wor#ing, or the

Aarrow Road


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Section 1!

-rganisation and Management

1!1 'aintenance of a road re$uires proper planning, programming and ade$uate tools, e$uipment,

machinery and s#illed wor#ers;operators to carry out the re$uired maintenance activities. There should

be well e$uipped dedicated maintenance units or divisions within the organi-ation in order to achieve

the intended purpose in an effective and efficient manner. /or primary roads, the nodal agency to

identify the priorities and initiate action related to maintenance implementation is either 'oRTE or

A


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accepted contract price. 'onthly lump sum payments are sub=ect to deductions if the re$uired

performance standard is not achieved. The deductions are effected as specified in the contract. < good

supervision is re$uired to ensure that there is no deficiency in the performance of maintenance and

condition of the roads and road assets included in the contract is maintained to the specified level.

1!!/or routine maintenance of low volume roads li#e village roads and 4Rs generally use of labor

based and semi mechani-ed methods are preferred.


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'ppendi 1

Pavement Condition 'ssessment= .isua& Surface Condition 'ssessment

"urface distress is a measure or indicator of the structural and resulting functional state of a pavement

structure and is generally given the prime importance by concerned agencies. Physical distress is

identified and a $uantitative visual assessment of distress is made by a well e0perienced; trained team of

%& persons while moving in a vehicle at a speed of 2*+ #m;hr.7hile recording the distresses the details for the following are visually noted and recorded in individual

percentage for each #m length in Proforma *.


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Proforma 1

.IS/' S/RF'C7 IS#R7SS M7'S/R7M70#

Aame of the Road1 Carriageway 7idth 9m)1

Chainage of Test "ection1 4ate of bservation1

Type of "urface1 7eather Condition1

Chainage Crac#s

Patch

7or# Potholes Bleeding 4epression

6dge

Brea#ing Raveling "hoving Rut 4epth

4rainage E

"houldercondition

Total/rom To 9>) 9>) 9>) 9>) 9>) 9>) 9>) 9>) 9mm)

Recorded by

Chec#ed by

67 | P a g e


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'ppendi 2

Pavement istress Measurements

In pro=ect level based maintenance strategies more precise condition data may be re$uired and hence

actual measurements of all the following distresses need to be measured in smaller representative

sections.

*.


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Crac#s with TypePatch 7or# Potholes Bleeding

4epression;

"ettlement6dge Brea#ing Raveling

Type"i-e 9m)

9F0B)


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'ppendi!

Met+odo&og$ for Pavement Condition Surve$

The surface condition of the pavement is mainly assessed in terms of roughness, pavement surface

distress in the form of crac#ing, Raveling, potholes, edge brea#, patch wor#, rutting, s#id resistance and

te0ture depth.

' Pavement Surface Roug+ness Measurements

The roughness of e0isting pavement is assessed in terms of Roughness Inde0 in mm;#m as per the

procedure given in IRC "P1 * ++& using /ifth 7heel Bump Integrator;


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7ith the recording of roughness, the distance tRavelllled is recorded so that the roughness can be

e0pressed in terms of specified length of road section, say per #m. Gsually the unevenness is e0pressed

in mm;#m. In order to facilitate recording of distance tRavelllled, an arrangement for measurement of

wheel revolutions is provided on the a0le of fifth wheel itself.

. Car '&e Mounted Bump Integrator

Car


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sensors used for measurement of longitudinal profile of the pavement surface. These sensors are placed

along the wheel path of survey vehicle. The system directly gives International Roughness Inde09IRI)

for both wheel paths of survey vehicle vi-. Feft IRI and Right IRI in terms of m;#m.

P+oto!: aser Profi&ometer Insta&&ed in Front of t+e Surve$ .e+ic&e

" Mer&in

'6RFIA 9'achine for 6valuating Roughness using Fowcost IAstrumentation) can be used either

for direct measurement or for calibrating responsetype instruments such as the vehiclemounted

bump integrator. It consists of a metal frame *.2 m long with a wheel at the front, a foot at the rear,

and a probe midway between them that rests on the road surface. The probe is attached to a moving

arm at the other end of which is a pointer that moves over a chart. The machine is placed at

successive locations along the road and the positions of the pointer are recorded on the chart to build

up a histogram. The width of this histogram can be used to give a good estimate of roughness in

terms of the International Roughness Inde0. < typical view of the e$uipment is shown in photo &.

P+oto": ' #$pica& .ie, of M7RI0


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% ipstic6'uto Read Road Profi&er

It is a precise electronic digital level and profiler. It stands on two support legs. ust by a simple twist

of the wrist it can ta#e readings along a survey line. It measures, displays and records the elevation

difference between front and the rear leg. The readings that are ta#en are accurate upto *++th

decimal place. It directly gives International Roughness Inde0 in m;#m. < typical view of the

e$uipment is shown in photo (.

P+oto %: ' #$pica& .ie, of ipstic6

. ;a&6ing Profi&er

The 7al#ing Profiler is a precision instrument designed to collect surface profile data. These data can be

used to accurately assess the characteristics and $uality of any continuous paved surface. Typically the

surface profile is used to generate a number of internationally recogni-ed roughness inde0, ride $uality

and pavement maintenance indices etc.

It is a precision surveying tool which is designed to operate at a moderate and steady wal#ing pace in a

straight line. The e$uipment has an integral Control Gnit which provides all the functions of instrument

calibration, survey setup and operator feedbac#. Fi#e 4ipstic#, it also directly gives International

Roughness Inde0 in m;#m. < typical view of the e$uipment is shown in photo .

P+oto 3: ' #$pica& .ie, of ;a&6ing Profi&er


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B Measurement of Pavement Surface istress

4istress is developed in the pavement surface in form of crac#ing, reveling, potholes, edge brea#, rut

depth, patch wor#, te0ture and etc. with passage of time due to a variety of influencing factors such as

traffic volume and loads and climatic conditions etc.

1 Manua& Met+od:

The measurements of pavement surface distress on fle0ible pavements are measured manually in terms

of area in s$uare meter, meter as given in


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The Portable "#id Resistance Tester can be conveniently used for measuring s#id resistance of

pavements. /or obtaining reliable results with this method, tests should be carried out at a carefully

selected representative locations.

"ide /orce Coefficient or cornering friction on paved surfaces using 'u'eter, a high speed device

for measuring s#id resistance.

"#id Trailor used for measuring bra#ing force coefficient of friction. This is also a high speed device

for measuring s#id resistance.

1 Porta&e S6id Resistance #ester (Britis+ Pendu&um #ester): This is a dynamic pendulum impact

type tester used to measure the energy loss when a rubber slider edge is propelled over a test surface.

The tester is suited for laboratory as well as field tests on flat surfaces and for polish value

measurements on curved laboratory specimens from the accelerated wheel tests. 9


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P+oto>: ' #$pica& .ie, of MuMeter

Measurement of #eture ept+

The macro te0ture depth is determined by sand patch method as per the clause +.* of "pecification

for Road and Bridge 7or#s!.

The macro te0ture in terms of 'ean Profile 4epth in mm can also be collected automatically using

modern laser based systems usually installed in


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Appendix

/ti&it$ for Rating of pavement ased on Auantit$ of distress:

< simple application in 'se0cel has been prepared for calculating the overall;final rating of the road

based on the $uantity 9>) of various distresses as per the ranges described in Table (.* to (.% earlier, for

different categories of roads. The application developed for all category of roads, is available to the users

in the C4 enclosed with this document.

This utility assigns the rating value to each individual parameter from *, *.* to .+ and .* to %.+ which

corresponds to Poor, /air and 3ood condition of the road respectively.

IRC-H-6-IRC-82-Final-Draft-15.01.2015.docx

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