SP–027 Manual for Assessment of Surface Defects …...Wheel track rutting can take the form of single or double rut in the wheel tracks after repeated load application. Wheel track

Materials and EngineeringResearch Office

Ministry ofTransportation

Highway StandardsBranch

Materials Engineeringand Research Office

SP–027 Manual for Assessment of SurfaceDefects of In-Place RecycledPavement Mats

Crown Copyright © 2015 Ministry of Transportation

Technical Report Documentation Page

Manual for Assessment of Surface Defects ofIn-Place Recycled Pavement Mats

Number: SP – 027 ISBN 978-1-4606-5625-9 (Print)ISSN 978-1-4606-5626-6 (PDF)

MinistryContact:

Materials and Engineering OfficeHighway Standard BranchProvincial Highway Management Division

(416) 235-3733Abstract: This Manual provides guidance for the assessment of surface defects and

distresses within an in-place recycled pavement mat prior to placement ofthe overlying hot mix layer(s). The assessment applies to the following in-place processes: Full Depth Reclamation with Expanded AsphaltStabilization (EAS), Cold In-place Recycling with emulsion (CIR) and ColdIn-place Recycling with Expanded Asphalt Mix (CIREAM).

The purpose of the Manual is to assist with the administration of contractrequirements related to the in-place recycling processes used in Ontarioand to achieve consistent assessment of surface appearance defects inaccordance with the applicable Ontario Provincial Standard Specifications(OPSS) and current Ministry Special Provisions.

Key Words: surface defects, distress, , in-place recycling, full depth reclamation withExpanded Asphalt Stabilization (EAS), Cold In-place Recycling withemulsion (CIR) and Cold In-place Recycling with Expanded Asphalt Mix(CIREAM).

Manual for Assessment of Surface Defects of In-Place Recycled Pavement Mats 2015

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Table of Contents

Preface ..........................................................................................................................................................4

Chapter 1 Introduction .............................................................................................................................5

Chapter 2 Distress Evaluation for CIR/CIREAM.........................................................................................6

2.1 Typical Mat.................................................................................................................................... 6

2.2 Ravelling or Coarse Aggregate Loss ..............................................................................................6

2.2.1 Definition...............................................................................................................................6

2.2.2 Severity ................................................................................................................................. 6

2.2.3 Examples ...............................................................................................................................7

2.3 Wheel Track Rutting....................................................................................................................10

2.3.1 Definition.............................................................................................................................10

2.3.2 Severity ...............................................................................................................................10

2.3.1 Examples .............................................................................................................................10

2.4 Segregation and Longitudinal Streak ..........................................................................................13

2.4.1 Definition.............................................................................................................................13

2.4.2 Severity ...............................................................................................................................13

2.4.3 Examples .............................................................................................................................13

2.4.4 Measurement of Segregation .............................................................................................15

Chapter 3 Distress Evaluation for EAS ....................................................................................................16

3.1 Typical Mat..................................................................................................................................16

3.2 Mats with Surface Defects ..........................................................................................................16

3.2.1 Ravelling or Coarse Aggregate Loss ....................................................................................17

3.2.2 Flushing ...............................................................................................................................19

3.2.3 Distortion ............................................................................................................................19

3.2.4 Wheel-Track Rutting ...........................................................................................................20

3.2.5 Wheel-Track Cracking .........................................................................................................20


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Preface

This Manual was prepared by the Pavements and Foundations Section of the Materials Engineering andResearch Office. The objective of this Manual is to provide guidance for the assessment of surfacedefects and distresses within in-place recycling pavement mats prior to placement of overlying hot mixcourse(s). The Manual is applicable to the following in-place recycling processes: Full Depth Reclamationwith Expanded Asphalt Stabilization (EAS), Cold In-place Recycling with emulsion (CIR) and Cold In-place Recycling with Expanded Asphalt Mix (CIREAM).

The Manual is primarily intended for use by the regional staff of the Ministry of Transportation as well asconsultants administering Ministry contracts. The purpose of the Manual is to assist with theadministration of contract requirements related to the in-place recycling processes used in Ontario and toachieve consistent assessment of surface appearance defects in accordance with the applicable OntarioProvincial Standard Specifications (OPSS) and current Ministry Special Provisions.

The Manual is referenced by the Specifications and Special Provisions and forms part of the contractbetween the Ministry and the Contractor. The Ministry and the Contractor are bound by the contents ofthis Manual unless agreed to in writing, in whole or in part, by both parties.


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Chapter 1 Introduction

The surface texture and material properties of In-place recycled pavement mats are unique and theoverall behaviour of the mat is different than that of a hot mix asphalt layer. Therefore referencing SP-024 Manual for Condition Rating of Flexible Pavements as a guide for recycled mat assessment is notappropriate for many of the defects and distresses identified using SP-24. The purpose of this manual isto provide guidance on how to define the defects and severity on the in-place recycling pavements. Thismanual defines the defects and distresses applicable to in-place recycled mats for the purpose ofdetermining acceptable mat texture, appearance and performance prior to placement of overlying hot mixasphalt layers.

The assessment of surface defects and distresses of in-place recycling pavement mats is furtherdifferentiated for CIR/CIREAM and EAS. CIR and CIREAM are partial depth reclamation processes ofthe existing HMA pavement layers and perform as a binder course in the pavement structure. Thesurface texture of CIR and CIREAM mats is similar and their assessment protocol is the same. ExpandedAsphalt Stabilization is a full depth reclamation process of existing granular and HMA pavement layers,EAS is referred to as a base stabilization process and its assessment protocol is different from the oneused for CIR/CIREAM mats.

Frequency of assessment of surface defects and distress should be continuous from the completion ofthe in-place recycling process to the overlaying of subsequent pavement course(s). It is understood thatthe surface condition of the pavements changes with time particularly when traffic is allowed on therecycled pavement surface. The in-place recycled mats should receive a final assessment immediatelyprior to the overlaying of the pavement course(s) to ensure that the surface appearance of the in-placerecycling pavements conforms to the requirements of the relevant specifications.


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Chapter 2 Distress Evaluation for CIR/CIREAM

The CIR and CIREAM mat will be evaluated for the presence of any surface distress such as ravelling orcoarse aggregate loss, wheel track rutting, segregation or longitudinal streaks, flushing or fat spots, etc.prior to HMA overlaying. The distress type and its severity will be identified in order to decide whether thesurface appearance of the CIR/CIREAM mat conforms to the specifications. The extent of the distress willbe recorded at site for the purpose of deciding the limit of the repair work.

2.1 Typical MatThe following is an example of a typical CIR/CIREAM mat with no ravelling or segregation:

Figure 1: Acceptable CIR/CIREAM Mat

2.2 Ravelling or Coarse Aggregate Loss

2.2.1 DefinitionLoss of Coarse Aggregates means pavement surface is breaking up into small pockmarks as coarseaggregate particles are lost from the surface.

Ravelling means progressive loss of pavement materials (coarse or fine aggregates, or both) fromsurface downward results in a pock-marked appearance.

2.2.2 SeverityVery Slight - Barely noticeable loss/lack of pavement materials.

Slight - Noticeable loss/lack of pavement materials.

Moderate - Having pock-marked appearance, fairly well spaced between pock-marks. Shallowdisintegration of pavement surface, an open-textured look.


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Severe – Having pock-marked appearance, pock-marks are closely spaced. Disintegration with lowseverity potholes.

Very Severe - Surface has a ravelled appearance and is disintegrated into moderate or high severitypotholes.

2.2.3 ExamplesThe following are examples of the CIR/CIREAM mat with ravelling or loss of coarse aggregates of variousseverity:

Figure 2: CIR/CIREAM Slight Coarse Aggregate Loss


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Figure 3: CIR/CIREAM Moderate Ravelling


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Figure 4: CIR/CIREAM Severe Ravelling

Figure 5: CIR/CIREAM Very Severe Ravelling


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2.3 Wheel Track Rutting

2.3.1 DefinitionWheel track rutting can take the form of single or double rut in the wheel tracks after repeated loadapplication. Wheel track rutting results from densification and permanent deformation under the load,combined with displacement of pavement materials. Deep ruts are often accompanied bylongitudinal cracking in the wheel tracks.

The rut depth shall be measured by placing a 1.2m straight edge cross the rut area perpendicular to thedriving direction, vertically placing a gauge with minimum 1mm graduation or finer to measure thegreatest distance between the pavement and the bottom of the straight edge.

2.3.2 SeverityVery Slight - Barely noticeable, the rut depth is 3 to 6 mm.

Slight - Rut depth is between 7 to 12 mm.

Moderate - Rut depth is between 13 to 19 mm or double rutting begins to develop.

Severe - Rut depth is between 20 to 25 mm or double rutting developed.

Very Severe - Rut depth is greater than 25 mm, with single or double rutting.

Very Severe - Rut depth is greater than 25 mm, with single or double rutting.

2.3.1 ExamplesThe following are examples of the CIR/CIREAM mat with wheel track rutting of various severity:


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Figure 6: CIR/CIREAM Very Slight Rutting

Figure 7: CIR/CIREAM Slight Rutting


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Figure 8: CIR/CIREAM Moderate Rutting

Figure 9: CIR/CIREAM Severe Rutting


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2.4 Segregation and Longitudinal Streak

2.4.1 DefinitionSegregation for CIR and CIREAM means a condition of the pavement characterized by areas withcomparatively coarser or finer texture than that of the surrounding pavement. Longitudinal streak is thesegregation which manifests itself as a longitude mark on the pavement mats caused by the impropersetting of the paver.

2.4.2 Severitya) Slight Segregation means the pavement matrix is in place between the coarse aggregate

particles; however, there are slightly more coarse aggregate particles in comparison with thesurrounding acceptable mix.

b) Medium Segregation means the pavement has significantly more coarse aggregate particlesthan the surrounding acceptable mat and usually exhibits some lack of surface matrix.

c) Severe Segregation means the pavement appears very coarse, with coarse aggregate particleagainst coarse aggregate particle and the pavement has little or no matrix.

2.4.3 ExamplesThe following are examples for segregation of various severity on CIR/CIREAM mats:

Figure 100: CIR/CIREAM Slight Segregation


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Figure 11: CIR/CIREAM Medium Segregation at Mid-lane

Figure 12: CIR/CIREAM Severe Segregation at Localized Area


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2.4.4 Measurement of SegregationThe degree of segregation can be measured at site following the procedure as described in Test MethodLS-317 to assess the severity of the segregation. The following Table 1 shows the allowablemacrotexture ratios for CIR and CIREAM mats.

Table 1 – Allowable Macrotexture Ratios for CIR/CIREAM Pavements

Mix TypeMaximum Allowable Macrotexture

Depth of Non-segregated Area(mm)

Macrotexture Ratio, MR

Degree of SegregationSlight Medium Severe

CIR/CIREAM 1.0 < 2.0 2.0 to 3.5 > 3.5


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Chapter 3 Distress Evaluation for EAS

The EAS mat will be evaluated for the presence of any surface distress such as ravelling or coarseaggregate loss, wheel track rutting, deformation, flushing or fat spots, etc. prior to the overlaying of thesubsequent pavement course(s). The distress type and its severity will be identified in order to decidewhether the surface appearance conforms to the specifications. The extent of the distress will berecorded at site for the purpose of deciding the limit of the repair work.

3.1 Typical MatThe following is an example of a typical EAS mat with no ravelling or segregation:

Figure 13: Typical EAS Mat

3.2 Mats with Surface DefectsThe following are examples of EAS mat with various types of surface defects:


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3.2.1 Ravelling or Coarse Aggregate Loss

Figure 14: EAS Slight Aggregate Loss

Figure 15: EAS Moderate Ravelling


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Figure 16: EAS Severe Ravelling

Figure 17: EAS Severe Ravelling into Pothole


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3.2.2 Flushing

Figure 18: EAS Moderate Flushing

3.2.3 Distortion

Figure 19: EAS Severe Surface Distortion


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3.2.4 Wheel-Track Rutting

Figure 20: EAS Severe Rutting

3.2.5 Wheel-Track Cracking

Figure 21: EAS Moderate Wheel-Track Cracking

Documents

SP–027 Manual for Assessment of Surface Defects …...Wheel track rutting can take the form of single or double rut in the wheel tracks after repeated load application. Wheel track