1. National Highway Institute Federal Highway Administration
PAVEMENT PRESERVATION: Selecting Pavements for Preventive Maintenance NHI Course #
This course is intended to introduce a very important part of the pavement preservation concept: determining when a pavement is a good candidate for a preventive maintenance (PM).
Have the participants and instructors introduce themselves.
Describe the roles of NHI, FHWA, and FP2 in sponsoring the development of this course.
National Highway Institute
Federal Highway Administration
Foundation for
Pavement
Preservation

2. NHI Pavement Preservation Courses
Course 1: The Preventive Maintenance Concept (No )
Course 2: Selecting Pavements for Preventive Maintenance (No )
Course 3: Design and Construction of Quality Preventive Maintenance Treatments (under development)
Course 4: Integrating Preventive Maintenance into Pavement Management Systems (under development)
It is first important to understand where this course fits in the series of NHI pavement preservation courses. This course is actually the second in a four-part series of pavement preservation courses being developed by NHI. Give some brief details of each course and describe the logical progression.
There are several other NHI courses that may be of interest to participants. While we will touch on parts of these subjects in this course, a more complete treatment of the subject can be found in these NHI courses:
Techniques for Pavement Rehabilitation.
PCC Materials.
Subsurface Drainage.
PCC Construction.
Distress Identification.

3. Course Organization Course Introduction
Introduction to Pavement Preventive Maintenance Concepts
Influence of Pavement Condition on Project Selection
Preventive Maintenance Treatments
Techniques for Determining Pavement/ Treatment Feasibility
The Selection Process
Summary and Review
This course is made up of seven different modules (the titles of which are shown here). Use this slide to give a brief synopsis of the scope of the course. A true introduction to the course starts with the next slide.

4. Session 1 Course Introduction
This first session presents a general overview of the course and the information to be covered.

5. Session 1 Objectives
Overview of pavement preservation and preventive maintenance
Overall course objectives
Course schedule, content, and format
Introduce course reference materials
Discuss the objectives of this first session. In session one we will:
First, give a brief overview of pavement preservation and preventive maintenance (focusing on explaining the differences between these terms).
Define the overall course objectives.
Present the course schedule and content, as well as discuss the format of the course (including the instructor’s expectations of the audience).
Introduce corresponding course reference materials that are provided to participants.

6. What is Pavement Preservation?
Pavement preservation is the sum of all activities undertaken to provide and maintain serviceable roadways, including preserving the investment in the national highway system, extending pavement life, enhancing pavement performance, ensuring cost-effectiveness, and reducing user delays.
The terms “pavement preservation” and “preventive maintenance” are often confused. It is important to understand the difference of each.
What is pavement preservation?
There has been much discussion over determining a consensual definition of pavement preservation. The broad definition shown here is the result of joint efforts of the AASHTO Lead States Team on Pavement Preservation, industry representatives, and FHWA. Basically, pavement preservation is the practice of selecting and applying maintenance and minor rehabilitation activities at appropriate times in order to achieve the goals listed here. Pavement preservation works by not only maintaining better pavement performance over the life of the pavement, but also extending the time until major restoration, rehabilitation, or reconstruction is required.
So, what treatments does this include? Ask the class what they think? There is no set answer that’s appropriate for all.
- Consensual definition from AASHTO, Industry Representatives, and FHWA

7. Components of Pavement Preservation
Includes all types of maintenance activities (i.e., routine, reactive, corrective, and preventive)
Includes minor rehabilitation activities
Does not include major rehabilitation or reconstruction
This slide shows the types of activities that are included under the definition of pavement preservation.
Note: each of the different types of maintenance activities will be discussed on the next slide. Also note, that preventive maintenance is only one component (although an important one) of pavement preservation.
Once a pavement has experienced significant structural deterioration and is in need of major rehabilitation, restoration, or reconstruction, it is no longer covered under the umbrella of pavement preservation.
Definitions:
Maintenance—relatively minor activities applied to an in-service pavement that are intended to “maintain” the structural integrity and functional pavement characteristics above a minimum level of service. Maintenance activities are typically classified as routine, reactive, corrective, or preventive.
Rehabilitation—more extensive work undertaken to return an existing roadway to an acceptable structural and functional condition (e.g., restoration, overlays).
Reconstruction—construction of the equivalent of a new pavement structure which usually involves complete removal and replacement of the existing pavement structure including new and/or recycled materials.

8. Types of Maintenance Activities
Planned?
Before Deterioration?
Extends Facility Life?
Routine
Yes
Not Necessarily
Sometimes
Reactive (Demand) No
Probably Not
Corrective
Generally
Preventive
What are the different types of maintenance activities that are part of pavement preservation? How do they differ? (Planned vs. not planned? Condition of pavement when applied? Does the applied maintenance activity extend the life of the facility?) The table summarizes information in Geoffroy’s NCHRP 223, “Cost-Effective Preventive Pavement Maintenance.”
Define the different types of maintenance (NCHRP 223):
Routine—Scheduled day-to-day maintenance activities (e.g., sealing cracks).
Reactive—Unscheduled maintenance activities in response to events beyond the control of the maintenance organization (e.g., pothole patching, patching pavement blowups, unplugging drainage facilities).
Corrective—Planned activities to repair deficiencies, restore elements of the highway to its original condition, or increase the service life of the facility elements (e.g., partial depth repairs of PCC pavements, patching or wedging of HMA pavements).
Preventive—Planned activities intended to “preserve” the system (i.e., arrest light deterioration, retard future deterioration, and reduce the need for routine, demand, and corrective maintenance). Note these activities add functional (not structural) value to the pavement (e.g., joint and crack sealing, surface treatments, thin overlays, and drainage maintenance). Note: if a preventive maintenance technique does not extend the life of the facility, it is most likely not cost-effective.
Additional Notes:
The instructor may want to draw a “typical” S-shaped performance curve on a white board for illustration.
The effects of corrective and routine maintenance is built into the “typical” performance curves.
Part of routine maintenance is preventive maintenance (depending on when it is applied).

9. What is Preventive Maintenance?
The planned strategy of cost effective treatments to an existing roadway system and its appurtenances that preserves the system, retards future deterioration, and maintains or improves the functional condition of the system (without increasing structural capacity).
This slide provides a more in-depth definition of preventive maintenance. Preventive maintenance is a tool for pavement preservation. Most agree that preventive maintenance is a concept that has really only been applied to pavements in this country within the last decade or so. This more formal definition of preventive maintenance was developed by AASHTO’s Standing Committee on Highways in 1997.
Not all common pavement problems (distresses) can be influenced by the application of preventive maintenance. Therefore, it is important to understand which common pavement problems (for both HMA- and PCC-surfaced pavements) are specifically avoided or minimized by applying effective preventive maintenance techniques. Note: “effective” preventive maintenance can be defined as a strategy in which the appropriate preventive maintenance techniques (treatments) are applied at a timing which maximizes service life while minimizing life-cycle costs.
The AASHTO Standing Committee on Highways has defined preventive maintenance as “The planned strategy of cost effective treatments to an existing roadway system and its appurtenances that preserves the system, retards future deterioration, and maintains or improves the functional condition of the system (without increasing structural capacity).” Although effective preventive maintenance has some positive effects on different structural problems, its main purpose is addressing potential or existing functional problems. What types of functional pavement problems develop with HMA-surfaced pavements? What types of functional problems occur with PCC-surface pavements?
- AASHTO’s Standing Committee on Highways

10. Introduction to Pavement Preventive Maintenance
What variables are typically considered in identifying a pavement’s need for…
Maintenance?
Rehabilitation?
Reconstruction?
What’s different with preventive maintenance?
Traditionally, maintenance has been reactive, rehabilitation was considered when the need for maintenance became too frequent, and reconstruction came as pavements were allowed to fail. So variables might include the type, severity, and extent of specific distresses, the pavement age, etc.
We have mentioned preventive maintenance a few times up until now, but what does the class really know about preventive maintenance? What does preventive maintenance mean to you? If the concept is summarized in “the right treatment on the right pavement, at the right time,” how do they determine what the right pavement is? Ask the audience how they select pavements for preventive maintenance? What do you look at to identify candidates? Prompt the audience about the following identifying factors:
Distresses? What types? What severities?
Age? What is a typical target age for PM candidates?
Expected rehabilitation?
Traffic levels?
Environmental factors?
Politics?
All factors typically involve looking forward to predict how a pavement will perform.

11. Candidate for…?
This next series of slides shows pavements at various states of their lives.
Is this pavement a candidate for preventive maintenance? What sort of information do we consider to help us to answer this question? Distress or pavement condition will play a major role, but there is going to be other information as well.
This photo shows a pavement with reactive aggregate (probably throughout the pavement). Therefore, this is most likely NOT a good candidate for PM (in a colder climate) because sealing such a pavement will cause the pavement to deteriorate. Note: environmental conditions would greatly influence whether such a pavement is a candidate for PM. In areas of mild climate (e.g., California), applying certain PM techniques (such as a thin HMA overlay) may be successful at extending service life.

12. Candidate for…?
Is this PCC pavement with no distress a good candidate for PM? Where is this pavement on the typical performance curve? What types of distresses would you be looking for to determine if this is a good PM candidate (e.g., transverse joint faulting, roughness [ride], friction, signs of pumping)?
Since this pavement shows little or no distress, it is most likely a good candidate for PM.
To determine the most appropriate timing of PM activities, you must predict how this pavement is going to perform over time.

13. Candidate for…?
What distresses do you see here? Pumping caused by erosion or loss of support beneath slab corners. Note: Of all of the water that gets into a pavement, it is estimated that 80 percent enters through the shoulder-lane joint.
Is this pavement a good candidate for PM? While this is a load-related distress, depending on the extent and severity of the distress we may be able to consider PM.
What would the objective of a PM treatment be in this instance? What PM techniques would you consider?
Could be a candidate for dowel retrofits (if extensive faulting and slab cracking are not present), grinding (if faulting is minimal), joint sealing, or undersealing.

14. Candidate for…?
What type of distress do you see here at this PCC pavement joint? Transverse joint faulting caused by poor or inadequate load transfer and/or loss of support.
Is this pavement a good candidate for PM? The faulting looks significant (possibly >0.25 inch) so the ride is going to be rough. If faulting is the only distress, this pavement may be a candidate for a combination of load transfer restoration (LTR) and diamond grinding. If other distresses are present it is likely a more suitable candidate for rehabilitation or even reconstruction. It would be important to know if this is an isolated joint. Without knowing the extent and severity of other distresses we can’t be sure.

15. Candidate for…?
This is a brand new HMA pavement with no distress. Is this pavement a good candidate? “Yes” because of its young age and excellent condition.
What types of PM activities would you consider? Surface treatments?
When would you expect to see deterioration (i.e., in how many years)? When do you expect to first apply PM? You would most likely want to estimate when this pavement would first start to show oxidization problems. The pavement would benefit from a PM application prior to the pavement reaching that point.

16. Candidate for…?
This HMA pavement is showing some significant fatigue cracking in the wheel paths. Is this pavement a good candidate? This pavement is not a good candidate for preventive maintenance as it is experiencing what appear to be “significant” structural failures. Significant structural failures exclude pavements from consideration for preventive maintenance as they clearly indicate that the preventive maintenance “window of opportunity” has passed.

17. Candidate for…?
The only distress that this HMA pavement is showing is raveling (some areas are quite significant). Is this pavement a good candidate for preventive maintenance?
“Yes,” this pavement is most likely a good candidate for preventive maintenance. Raveling is a distress that can be addressed (as well as prevented) with different preventive maintenance techniques. Although this pavements functional performance will currently benefit from the application of a PM treatment, ideally it should have received a PM treatment before it was allowed to deteriorate to this condition (a true preventive application).

18. Summary of Preventive Maintenance Characteristics
Is a planned strategy
Uses cost-effective treatments
Applied when no or minimal deterioration exists
Maintains or improves functional condition
Delays major rehabilitation (extends pavement life)
Leads to improved customer satisfaction
Use this slide to refine the characteristics/definition of preventive maintenance.
Now is a good time to go into a discussion of each of these. What does the concept of a planned strategy mean (this is the opposite of a “worst-first” approach)? What defines cost effectiveness (the cheapest is not always the most cost-effective)? Note, only “functional” condition is improved by preventive maintenance (i.e., no structural benefit). What defines functional condition (ride and friction)? What would improvements consist of? What measures of customer satisfaction are affected?
Make the point that preventive maintenance is arguably the most important component of developing a complete pavement preservation approach, as it is focused on applying the most cost effective series of well performing, safe, and comfortable pavements. (Note: Pavement Preservation is defined in the FP2 glossary of terms as “the sum of all activities taken to provide and maintain serviceable roadways. This includes corrective maintenance and preventive maintenance, as well as minor rehabilitation projects.”)

19. Overall Course Objectives
Identify pavement conditions and other attributes that suggest whether PM is appropriate
Identify feasible treatments for the selected pavement
Select a treatment based on consideration of life-cycle costs, improved performance, anticipated benefits, and other factors
There are three major objectives for this course.
What do participants remember as a definition of preventive maintenance? Discuss how it applies to the agency’s current practices. How many components of a preventive maintenance program do they currently have? How do the course objectives fit in with the agency’s current practices? Do they tie in or are they leading?
When mentioning the third objective, you may want to briefly define what is meant by the consideration of life-cycle costs (i.e., the types of costs that are included, and the lower the costs the better).

20. Course Schedule and Content
DAY ONE
Session 1: Course Introduction
Session 2: Introduction to Pavement Preventive Maintenance Concepts
Session 3: Influence of Pavement Condition on Project Selection
Workshop 1: Evaluating Pavements for Preventive Maintenance
Session 4: Preventive Maintenance Treatments

21. Course Schedule and Content (continued)
DAY TWO
Session 5: Techniques for Determining Pavement/Treatment Feasibility
Workshop 2: Identifying Feasible Treatments and Strategies
Session 6: The Selection Process
Workshop 3: Determining the Most Appropriate PM Strategy
Session 7: Summary and Review

22. Course Format Lecture/discussion Workshops Protocol: Informal
Questions are encouraged
Class participation is essential

23. Workshops Opportunity to apply course concepts Interactive sessions
Evaluating pavement condition and pavement selection
Identifying feasible treatments
Selecting treatments
The workshops are a key part of the class. They provide the participants an opportunity to apply course concepts and procedures to example problems.

24. Course Reference Materials
Pavement Preservation: The Preventive Maintenance Concept— Reference Manual
Pavement Preservation: Selecting Pavements for Preventive Maintenance—Participant’s Workbook
There are two course reference materials that will be useful to the participants. The Reference Manual was developed as an overview of preventive maintenance and includes a lot of information on the concept. The Participant’s Workbook contains information for the participant to follow along during the presentations.

25. Other Related Research
NCHRP 14-14: Optimal Timing of Preventive Maintenance
NCHRP (02): LTPP Data Analysis: Relative Performance of JPCP with Sealed and Unsealed Joints
NCHRP (03/04): LTPP Data Analysis: Effectiveness of Maintenance and Rehabilitation Options
ADOT preventive maintenance test sections
There is also some ongoing research that should be of interest to participants. At this point the instructor should discuss each of these projects in greater detail, including what the project is looking at and what it is intended to produce.
Additional Notes: may want to define LTPP (Long-Term Pavement Performance) and JPCP (jointed plain concrete pavement).