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Perspectives |
Pavement MaintenanceLong-term Strategies for Protecting Your Investment Like every other asset, pavement
systems should be periodically maintained to extend their life and reduce
costs. Unfortunately, too often we do
nothing until the pavement reaches the end of its service life and
rehabilitation or reconstruction has to be conducted to restore its
serviceability. Even in cases where
budgets have been proposed for maintenance, many decisions are often reactive
in nature. The following overview explains the
importance of having a long-term strategy for maintaining pavement in a
cost-effective manner. Types of Maintenance
Preventive Maintenance is a strategy intended to retard progressive failures and
maximize an owner’s return on investment by extending the life cycle of the
pavements. Preventive maintenance
activities include cracksealing, localized repairs,underdrain installations
and a variety of surface treatments. Scheduled Maintenance is performed to correct a specific pavement or area of
distress, such as surface deformation, extensive cracking and localized areas
of failure. Typical scheduled
maintenance activities include restorations, patches, installation of
underdrains, structural overlays, and reconstruction. Preventive maintenance is a long-term
solution relative to scheduled maintenance.
As indicated in the graphic
above, the main differences are the cost and the condition of the pavement
when treatment is applied. Preventive
maintenance is performed when the pavement is still in good condition, while
scheduled (corrective) maintenance is performed when the pavement is in
greater need of repair due to lack of a preventive maintenance strategy or
improper construction. How to Choose Maintenance Type and Time Individuals and firms that are
experienced in pavement management programs are able to identify multiple
strategies that are reflective of the pavement condition and the client’s
intended use. Performing an inappropriate repair (either method or timing)
is not only a waste of money, but can also promote the rate of distress
development. Generally, when the
pavement is in good condition, inexpensive preventive maintenance treatments
are cost-effective. As pavement ages
and the amount of deterioration increases, the effectiveness of preventive
maintenance such as cracksealing and surface treatment decreases. Therefore, the maintenance strategy should
be adjusted accordingly. As the pavement ages,
development of a scheduled maintenance program is imperative. From a pavement management point of view, a
condition survey and non-destructive testing (NDT) methods can be performed
to provide a more rational approach to determine which pavement section needs
treatment and when the appropriate treatment should be done. Why Preventive Maintenance is Important Preventive maintenance is generally
planned and cyclical in nature. The
primary objective of cracksealing and underdrains is to protect the pavement
structure from moisture that will reduce its load bearing capacity. The timely use of a surface treatment can
effectively prevent premature pavement deterioration, by minimizing the effects
of oxidation, raveling and surface cracking from developing. Effective preventive maintenance will
eventually delay pavement failures by reducing the long-term cost.
Studies show that preventive maintenance, when applied at the
appropriate time, is 3 to 6 times more cost-effective than providing no
preventive maintenance. Although
preventive maintenance is not performed to improve the load-carrying capacity
of a pavement, it extends the pavement’s useful life and level of
serviceability, resulting in substantial life-cycle cost savings. When to Apply Preventive
Maintenance Waiting until after a failure occurs is
not considered preventive maintenance and is not cost-effective. The effectiveness of a preventive
maintenance treatment is directly related to the conditions of the pavement. Conducting preventive maintenance
activities on a sound pavement in good condition will be very effective in
prolonging that pavement’s service life.
Once moderate to severe distresses can be visually observed, it is
typically too late for preventive maintenance techniques to be a
cost-effective use of money. Preventive maintenance methods are
typically designed to repair environmental related distresses. Environmental conditions remain fairly
consistent over time, so the maximum time span between preventive maintenance
treatments should be based on time, traffic or usage. Good maintenance, especially systematic preventive
maintenance, is the key to keeping pavement in good condition in a
cost-effective manner over its entire life-cycle. Don’t wait until your pavement becomes a
major concern. Select the right
maintenance activities and apply them to the right place at the right
time. If done correctly, you will get
the best return from your investment. Copyright (c) 2005, Benchmark,
Inc., all rights reserved. |
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