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In a municipal road and street
network, intersections are the most susceptible areas to pavement
deterioration. Heavy vehicles stopping and turning can damage
pavement surface severely, especially along the approaches to
intersections. The pavement within the junction of an intersection
also receives twice the traffic of the payment on the approach legs.
Bus pads are another area where distresses occur also because of the
damage resulting from turning and stopping on flexible pavements.
Many state, city,, and county
agencies use concrete, but others may be hesitant to consider it
because they believe it costs too much, is too difficult to repair,
or takes too long to place.
The truth is concrete pavements are
well-suited to handling the heavy, channelized traffic and turning
movements of vehicles. Concrete does not rut, washboard, or shove,
which makes it a safer, more durable pavement surface.
Lower Costs
 Although concrete pavements may
cost more, initially, than asphalt, there are many applications
where first costs are competitive.
Regardless of first costs, concrete
is almost invariably less expensive to own because of the reduced
maintenance and rehabilitation costs over the pavement's life cycle.
Life-cycle cost analysis (LCCA), or the projected costs to manage an
asset over its lifetime, involves the right combination of
engineering judgment and economic factors to calculate the true
costs of a pavement over a projected lifetime. LCCA simple projects
long-term costs, and then discounts to present values.
Open to Traffic in Hours
Concrete pavements no longer require
weeks to construct and open to traffic. Current paving methods and
materials mean that pavements can be opened sooner than the time that transpires between rush hours.
Not only does this reduce
construction time, it also reduces congestion and could help reduce
the more than 100,000 work-zone accidents that occur in the United
States each year. Processes such as fast-track technology, which
uses high early-strength cement and accelerating admixtures, can
allow concrete pavements to be opened in four hours or less. Also,
because concrete pavements require only one pass of the paver or
screed, instead of having to build up the pavement in multiple
layers, the construction time is often much less than asphalt
materials.
Construction Under Traffic
In addition to opening traffic
sooner, the concrete pavement industry has developed strategies for
managing traffic through construction work zones.
Ease of Repair
All pavements, regardless of type,
will eventually require repair. Concrete pavements can be repaired
easily with readily available equipment and materials. Experience
has shown that it's best to repair concrete with concrete.
Full-depth concrete repairs provide a permanently smooth transition
that can withstand traffic loads without settlement or deformation. |
