Session 4Session 4

Preventive Preventive Maintenance Maintenance TreatmentsTreatments

Learning ObjectivesLearning Objectives

1.1. Identify typical preventive Identify typical preventive maintenance techniques used on maintenance techniques used on HMA and PCC pavementsHMA and PCC pavements

2.2. Identify the purpose/effectiveness Identify the purpose/effectiveness and feasibility of preventive and feasibility of preventive maintenance treatmentsmaintenance treatments

Upon completion of this module, you Upon completion of this module, you will be able to:will be able to:

Preventive Maintenance Preventive Maintenance TreatmentsTreatments

Available treatmentsAvailable treatments HMA pavementsHMA pavements PCC pavementsPCC pavements

Purpose of individual treatmentsPurpose of individual treatments

Acceptable pavement conditions for Acceptable pavement conditions for application (feasibility)application (feasibility)

PM Techniques for PM Techniques for HMA-Surfaced PavementsHMA-Surfaced Pavements

HMAHMA

Preventive Maintenance Preventive Maintenance Technique TypesTechnique Types

Crack treatmentsCrack treatments

Surface treatmentsSurface treatments

Recycling treatmentsRecycling treatments

Milling and thin HMA overlaysMilling and thin HMA overlays

Maintenance of drainage featuresMaintenance of drainage features

HMAHMA

Crack TreatmentsCrack TreatmentsPurpose

Used to prevent Used to prevent water and debris water and debris from entering from entering individual cracks in individual cracks in the HMA the HMA pavement surfacepavement surface

HMAHMA

Crack SealingCrack Sealing

Distress TypeFatigue Cracking

Linear & Block Cracking“Stable” Rutting

RavelingFlushing/Bleeding

RoughnessFriction Loss

Moisture DamageShoving

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Surface TreatmentsSurface TreatmentsPurpose

Typically used to:Typically used to:

Seal cracksSeal cracks

Waterproof surfaceWaterproof surface

Improve frictionImprove friction

Improve rideabilityImprove rideability

Rejuvenate Rejuvenate surfacesurface HMAHMA

Surface TreatmentsSurface TreatmentsTypesTypes

Fog sealFog seal

Slurry sealSlurry seal

MicrosurfacingMicrosurfacing

Chip sealChip seal

Scrub sealScrub seal

Ultrathin friction courseUltrathin friction course

Others?Others?HMAHMA

Light application of diluted, slow-setting asphalt emulsion without aggregate cover

Description

Purpose Seal pavement Inhibit raveling Enrich hardened/oxidized asphalt Provide delineation with shoulder

Fog SealFog Seal

HMAHMA

Fog SealFog Seal

Distress TypeFatigue Cracking

Linear & Block Cracking“Stable” Rutting

RavelingFlushing/Bleeding

RoughnessFriction Loss

Moisture DamageShoving

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Slurry SealSlurry Seal

Mixture of well-graded aggregate and slow setting asphalt emulsion

Description

Purpose Seal surface cracks Correct raveling/oxidation Fill minor surface irregularities and

restore frictionHMAHMA

Slurry SealSlurry Seal

Distress TypeFatigue Cracking

Linear & Block Cracking“Stable” Rutting

RavelingFlushing/Bleeding

RoughnessFriction Loss

Moisture DamageShoving

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

MicrosurfacinMicrosurfacingg

Mixture of high-quality aggregates and polymer-modified emulsion binder

Description

Purpose Inhibit raveling and surface oxidation Improve surface friction Fill ruts/minor surface irregularities Seal pavement surface

HMAHMA

MicrosurfacingMicrosurfacing

Distress TypeFatigue Cracking

Linear & Block Cracking“Stable” Rutting

RavelingFlushing/Bleeding

RoughnessFriction Loss

Moisture DamageShoving

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Chip SealChip Seal

Application of asphalt and aggregate chips rolled onto the pavement

Purpose Seal pavement Enrich hardened/oxidized asphalt Retard reflection cracking on HMA overlays Improve surface friction

Description

HMAHMA

Chip SealChip Seal

Distress TypeFatigue Cracking

Linear & Block Cracking“Stable” Rutting

RavelingFlushing/Bleeding

RoughnessFriction Loss

Moisture DamageShoving

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Scrub SealScrub Seal

Application of sand or small-sized aggregate on broomed layer of polymer-modified asphalt

Purpose Fill and seal small cracks and voids Enrich hardened/oxidized asphalt Preparation for another treatment

Description

HMAHMA

Scrub SealScrub Seal

Distress TypeFatigue Cracking

Linear & Block Cracking“Stable” Rutting

RavelingFlushing/Bleeding

RoughnessFriction Loss

Moisture DamageShoving

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Ultrathin Friction Ultrathin Friction CourseCourse

Gap-graded, polymer-modified HMA placed on a heavy, polymer-modified emulsified asphalt tack coat

Purpose Increase surface friction Address surface distress Reduce noise

Description

HMAHMA

Ultrathin Friction CourseUltrathin Friction Course

Distress TypeFatigue Cracking

Linear & Block Cracking“Stable” Rutting

RavelingFlushing/Bleeding

RoughnessFriction Loss

Moisture DamageShoving

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Recycling TreatmentsRecycling TreatmentsPurpose

Typically used to:Typically used to:

Rework HMA to a HMA to a depth of 50 to 100 depth of 50 to 100 mm (2 to 4 inches)mm (2 to 4 inches)

Correct surface distressesCorrect surface distresses

Improve profile, crown, and slopeImprove profile, crown, and slope

HMAHMA

Recycling TreatmentsRecycling TreatmentsTypesTypes

Cold In-Place Recycling (CIR)Cold In-Place Recycling (CIR)

Hot In-Place Recycling (HIR)Hot In-Place Recycling (HIR)

HMAHMA

Cold In-Place Cold In-Place RecyclingRecycling

Milling, rejuvenating, and replacement of the top portion of the HMA surface (performed without heat)

Purpose Rework HMA to depth of 50 to 100 mm Correct surface distresses Improve profile, crown, and cross-slope

Description

HMAHMA

Hot In-Place Hot In-Place RecyclingRecycling

Milling, rejuvenating, and replacement of the top portion of the HMA surface (performed with heat)

Purpose Rework HMA to depth of 25 to 50 mm Correct surface distresses Improve profile, crown, and cross-slope

Description

HMAHMA

Cold and Hot In-Place RecyclingCold and Hot In-Place Recycling

Distress TypeFatigue Cracking

Linear & Block Cracking“Stable” Rutting

RavelingFlushing/Bleeding

RoughnessFriction Loss

Moisture DamageShoving

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Milling with Thin Milling with Thin HMA OverlayHMA Overlay

Application of a new HMA wearing course after milling of the top portion of the HMA surface

Purpose OGFC reduce hydroplaning and tire splash Improve rideability and surface friction Improve profile, crown, and cross-slope

Description

HMAHMA

Milling with Thin HMA OverlayMilling with Thin HMA Overlay

Distress TypeFatigue Cracking

Linear & Block Cracking“Stable” Rutting

RavelingFlushing/Bleeding

RoughnessFriction Loss

Moisture DamageShoving

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Maintenance of Drainage Maintenance of Drainage FeaturesFeatures

Any activity that will improve the drainability Any activity that will improve the drainability of a pavement sectionof a pavement section

Description

PurposeMinimize time to remove infiltrated or surface water

Recommended UseStrongly recommended on all HMA

pavements HMAHMA

PM Techniques for PM Techniques for PCC-Surfaced PavementsPCC-Surfaced Pavements

PCCPCC

Common PM Techniques Common PM Techniques for PCC-Surfaced for PCC-Surfaced

PavementsPavements Joint/crack sealingJoint/crack sealing

Diamond grindingDiamond grinding

Diamond groovingDiamond grooving

UndersealingUndersealing

Load transfer restorationLoad transfer restoration

Maintenance of drainage featuresMaintenance of drainage featuresPCCPCC

Joint/Crack Joint/Crack SealingSealing

Application of a sealant material in concrete pavement joints and cracks

Purpose Minimize moisture infiltration Prevent intrusion of incompressibles

Description

PCCPCC

Joint/Crack SealingJoint/Crack Sealing

Distress TypeLinear CrackingCorner Breaks

Transverse Joint FaultingJoint Spalling

D-CrackingPumping

RoughnessFriction Loss

Surface Distress

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Diamond Diamond GrindingGrinding

Removal of a thin layer of PCC using stacked diamond tipped cutting blades

Purpose Remove faulting Improve surface rideability Improve surface friction

Description

PCCPCC

Diamond GrindingDiamond Grinding

Distress TypeLinear CrackingCorner Breaks

Transverse Joint FaultingJoint Spalling

D-CrackingPumping

RoughnessFriction Loss

Surface Distress

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Diamond Diamond GroovingGrooving

Creation of narrow grooves in the PCC surface using diamond tipped cutting blades (localized areas)

PurposeReduce hydroplaning and wet weather accidents

Description

PCCPCC

Diamond GroovingDiamond Grooving

Distress TypeLinear CrackingCorner Breaks

Transverse Joint FaultingJoint Spalling

D-CrackingPumping

RoughnessFriction Loss

Surface Distress

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

UndersealingUndersealing

Pressure insertion of flowable material beneath a PCC slab

Purpose Fill underlying voids (not raise slab) Reduce pavement deflections Minimize pumping and faulting

Description

PCCPCC

UndersealingUndersealing

Distress TypeLinear CrackingCorner Breaks

Transverse Joint FaultingJoint Spalling

D-CrackingPumping

RoughnessFriction Loss

Surface Distress

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Load-Transfer Load-Transfer RestorationRestoration

Placement of load transfer devices across joints or cracks in an existing pavement

Purpose Provide reliable load transfer Reduce or eliminate pumping, faulting,

and corner breaks (reducing deflections)

Description

PCCPCC

Load-Transfer RestorationLoad-Transfer Restoration

Distress TypeLinear CrackingCorner Breaks

Transverse Joint FaultingJoint Spalling

D-CrackingPumping

RoughnessFriction Loss

Surface Distress

Extent of ProblemMinor Major

HMAHMA

Feasible

Not Appropriate

FeasibilityFeasibility

Effective

Marginal

No Impact

EffectivenessEffectiveness

Maintenance of Drainage Maintenance of Drainage FeaturesFeatures

Any activity that will improve the drainability Any activity that will improve the drainability of a pavement sectionof a pavement section

Description

PurposeMinimize time to remove infiltrated or surface water

Recommended UseStrongly recommended on all PCC

pavements PCCPCC

Other PM Techniques?Other PM Techniques?

Do you use Do you use any any techniques techniques other than other than those listed?those listed?

PM Techniques PM Techniques for Shoulders?for Shoulders?

What’s What’s different?different?

What’s the What’s the same?same?

Review of Learning Review of Learning ObjectivesObjectives

1.1. Identify typical preventive Identify typical preventive maintenance techniques used on maintenance techniques used on HMA and PCC pavementsHMA and PCC pavements

2.2. Identify the purpose/effectiveness Identify the purpose/effectiveness and feasibility of preventive and feasibility of preventive maintenance treatmentsmaintenance treatments