From Maintenance Technical

1
Chapter 4Joint Resealing and Crack Sealing

• From Maintenance Technical
• Advisory Guide (MTAG)

2
Learning Objectives

• List the benefits of joint resealing and crack
  sealing
• List the desirable sealant properties and
  characteristics
• Describe recommended installation procedures
• List important quality control activities
• Describe potential construction and performance
  problems
• Identify troubleshooting solutions

3
Presentation Outline

• Introduction
• Material selection and reservoir design
• Construction
• Quality control
• Troubleshooting

4
Introduction

• Definition

Placement of an approved sealant material in an
existing joint or crack to reduce moisture
infiltration and prevent intrusion of
incompressibles
5
PCC Pavement DeteriorationInfluence of Moisture
Infiltration
Cracks/Joints Moisture Infiltration
Loss of Fines (Pumping)
Corner Breaks
Transverse Joint Faulting
6
PCC Pavement DeteriorationInfluence of Moisture
Infiltration
Deteriorated Cracks

• Cracks
• Moisture Infiltration

7
PCC Pavement DeteriorationInfluence of
Incompressibles
Cracks/Joints Incompressible Material
Joint Spalling
Blow-Ups
8
PCC Joint ResealingCurrent Practice

• Debate to seal or not to seal
• Some believe the benefits do not offset the costs
  
• Most states seal transverse joints
• Recommendation continue to reseal joints if they
  were originally sealed!

9
Guidelines for Resealing Joints

• Sealant no longer functional
• Pavement not severely deteriorated
• Performed with other CPR activities
• Moderate installation temperatures
• Proper material selection and joint preparation
  is essential

10
Guidelines for Sealing Cracks

• Seal working transverse cracks
• Can seal cracks 13 mm (0.5 in) wide
• Use special crack-sawing blades
• Same general joint resealing procedures apply to
  crack sealing

11
Design, Materials Specifications
Module 4-1

• From Maintenance Technical
• Advisory Guide (MTAG)

12
Material Selection

• Sealant
• Thermoplastic materials
• Thermosetting materials
• Backer rod

13
Sealant MaterialThermoplastic Materials

• Rubberized asphalt
• Low modulus rubberized asphalt
• PVC coal tar

14
Sealant MaterialThermosetting Materials

• Polysulfide
• Polyurethane
• Silicone (non-sag)
• Silicone (self-leveling)

15
Sealant MaterialDesirable Sealant Properties
16
Sealant Material Performance

• Varies greatly with material type
• Quality of installation procedures
• Design factors affecting performance
• Joint movement
• Sealant properties
• Shape factor

17
Material Selection Factors

• Climate conditions
• Traffic level and percent trucks
• Crack extent and severity
• Contractor experience
• Safety concerns
• Material availability and cost

18
Joint Reservoir DesignCommon Configurations
19
Joint Reservoir Design
3.2 to 6.4 mm (0.125 to 0.25 in) recess
Sealant
Width
Thickness
(W)
(T)
Sealant
20
Joint Reservoir DesignRecommended Shape Factors
21
Sealant and Related Specs
http//www.dot.ca.gov/hq/esc/oe/specifications/SSP
s/2006-SSPs/
22
Typical Item Codes
http//i80.dot.ca.gov/hq/esc/oe/awards/item_code
23
Construction and Inspection
Module 4-2

• From Maintenance Technical
• Advisory Guide (MTAG)

24
Construction Joint Resealing
25
Construction Joint ResealingProcedure

• Sealant removal
• Joint refacing
• Joint cleaning
• Backer rod installation
• New sealant installation

26
Construction Joint ResealingSealant Removal
with Joint Plow
27
Construction Joint ResealingJoint Refacing
28
Construction Joint ResealingRefacing Blades
29
Construction Joint ResealingSandblasting
30
Construction Joint ResealingWaterblasting
31
Construction Joint ResealingCompressed Air
32
Construction Joint ResealingBacker Rod
33
Construction Joint ResealingBacker Rod
Installation
34
Construction Joint ResealingInstalled Backer Rod
35
Construction Joint ResealingThermoplastic
Sealant Installation
36
Construction Joint ResealingSilicone Sealant
Installation
37
Construction Joint Resealing Longitudinal
PCC/PCC Joints

• Tied non-working joint
• Hot-poured thermoplastic materials
• Reservoir not always formed

38
Construction Joint Resealing Longitudinal
PCC/PCC Joints
39
Construction Joint Resealing Longitudinal
PCC/HMA Joints

• 25-mm (1-in) width (min.) and depth
• No backer rod required
• Hot-pour and silicone sealants

40
Construction Joint Resealing Longitudinal
PCC/HMA Joints
41
Construction Joint Resealing Longitudinal
Sawcutting
42
Construction Joint Resealing Sawed Longitudinal
Joint Reservoir
43
Construction Joint Resealing Installation of
Sealant
44
Construction Joint Resealing Sealed PCC/HMA
Longitudinal Joint
45
Construction Crack Sealing
46
Construction Crack Sealing Procedure

• Crack sawing
• Cleaning
• Backer rod Installation
• Sealant installation

47
Construction Crack Sealing Crack Sawing
48
Construction Crack SealingCompleted Crack Seal
49
Presentation Outline
?

• Introduction
• Material selection and reservoir design
• Construction
• Quality control
• Troubleshooting

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50
Quality Control

• Sealant preparation
• Surface preparation
• Placement conditions
• Method of application
• Curing
• Opening to traffic

51
Quality ControlClass Exercise

• Break into three groups
• Pre-Seal considerations
• Equipment considerations
• Project inspection considerations
• Rate QC items as Required, Desired, or Not
  Necessary
• Use Reference Manual, checklist, and your
  experience

52
Project Checklist

• Preliminary Responsibilities
• Project review
• Document review
• Materials Checks
• Sealant
• Primer
• Backer rod
• General

53
Project Checklist

• Equipment Inspections
• Hot-applied sealant melters
• Cold-applied sealant pumps
• Joint leaning equipment
• Other equipment
• Others
• Weather requirements
• Traffic control

54
Project Checklist

• Project Inspection Responsibilities
• Joint preparation
• Backer material installation
• Hot-applied sealant installation
• Cold-applied sealant installation
• Preformed sealant installation
• Opening the pavement to traffic
• Cleanup Responsibilities

55
Presentation Outline
?

• Introduction
• Material selection and reservoir design
• Construction
• Quality control
• Troubleshooting

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?
56
Troubleshooting

• Construction quality and performance problems
• Approach

57
TroubleshootingWhat is wrong here?
Too Much Applied Sealant
58
TroubleshootingWhat is wrong here?
Dirt on Refaced Surfaces
59
TroubleshootingPossible Construction Problems

• Problem

Bubbles in hot applied sealant material

• Potential causes?

60
TroubleshootingPossible Construction Problems

• Problem

Irregularities in surface of tooled sealant

• Potential causes?

61
TroubleshootingPossible Construction Problems

• Problem

Tracking of material

• Potential causes?

62
TroubleshootingPossible Construction Problems

• Problem

Punctured or stretched backer rod

• Potential impact on performance?

63
TroubleshootingPossible Construction Problems

• Problem

Burrs along sawed edge

• Potential impact on performance?

64
Troubleshooting Guide Causes and Solutions

• Dust, dirt, or contamination on refaced joint or
  crack surfaces.
• Bubbles in hot-applied sealant material.
• Punctured or stretched backer rod.
• Raveling, spalling, or other irregularities of
  the joint walls prior to sealant application.
• Difficulty in installing sealant material.
• Tracking of material (i.e., the transfer of
  sealant material onto unwanted areas of the
  surface area via shoes, tires, and so on).
• Bumps or irregularities in surface of tooled
  sealant application.

65
Presentation Outline
?

• Introduction
• Material selection and reservoir design
• Construction
• Quality control
• Troubleshooting

?
?
?
?
66
Review Learning Objectives

• List the benefits of joint resealing and crack
  sealing
• List the desirable sealant properties and
  characteristics
• Describe recommended installation procedures
• List important quality control activities
• Describe potential construction and performance
  problems
• Identify troubleshooting solutions