|
SERVICES | STREET
MAINTENANCE
The following describes our pavement maintenance programs.
If you have further questions after reading this and the Frequently
Asked Questions, you can contact us for further assistance.
One of the responsibilities of the City of San Jose,
Department of Transportation is pavement maintenance. The goal of this
service is to effectively and economically preserve the City's 2,260 miles
of streets. Roads generally break up because preventive maintenance work
was not done in a timely manner, there is more and heavier traffic on
the roadway than it was built to handle, or the soil beneath the roadway
fails.
Pavement maintenance services are provided under three
programs to preserve and repair roadways:
I. Preventive
Maintenance , which includes
- Chip Sealing
- Slurry Sealing and
- Resurfacing
II. Pavement
Reconstruction
III. Emergency
Services
Preventive
Maintenance
Preventive maintenance, if performed before the road begins to break up,
is the most cost-effective of the three programs. Its purpose is to extend
the life of the road and to keep it looking and riding, as much as possible,
in like-new condition. The work performed under the preventive maintenance
program is called chip sealing, slurry sealing and resurfacing. The purpose
is to stop water from entering the roadway, which causes early break up
of the road surface. The useful life of roads can be extended from 20
to as much as 100 years if, on a regularly scheduled basis, small breaks
are fixed and a seal coat or resurfacing is done before more severe damage
occurs. This is the reason why maintenance work is sometimes done on streets,
that appear to be in good condition.
Back to top
Chip Sealing
Chip sealing is the application of crushed rock (gravel) over an emulsified
asphaltic oil. The oil seals the pavement from water penetration while
the gravel provides a wearing surface to protect the oil seal from traffic.
The oil is sprayed on the pavement first, immediately followed by replacement
of gravel. Compaction rollers then go over the gravel to seat it in the
oil. After a few days, power sweepers pick up any excess gravel. Another
follow-up sweeping is done within one month to remove gravel loosened
by traffic. Ideally, local streets should be chip sealed approximately
every ten years.
Back to top
Slurry Sealing
Slurry seal is a mixture of fine aggregate (sand-like) with emulsified
asphaltic oil. This mixing is done in a specially equipped slurry-seal
truck, then the slurry mix is spread on the pavement. Slurry sealing is
usually done on streets with higher traffic volumes and speeds because
it provides a smoother ride and avoids the problems associated with flying
gravel caused by higher speed traffic. Major streets should be slurry
sealed approximately every eight years.
Back to top
Resurfacing
Resurfacing is the application of two to four inches of asphalt over an
existing pavement to provide a smooth surface and add strength to the
road. On most of our resurfacing work, prior to placing the new asphalt,
a specially designed polyester fabric is placed over the old road to seal
the surface and prevent cracks from reflecting through the new asphalt.
Major streets have priority for resurfacing because they serve the greatest
number of people.
Back to top
Pavement Reconstruction
When the condition of a street reaches the point where preventive maintenance
is no loner cost-effective, then the street is put on the reconstruction
list. Reconstruction involves removing the entire roadway and replacing
it.
Back to top
Emergency Services
Emergency services are provided to remove hazards to traffic. Hazardous
conditions are radio dispatched for immediate repair or barricading. Conditions
that are not an immediate hazard are scheduled along with other repair
work.
Back to top
For more information or to report a pavement problem
call (408) 277-4373.
|
