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71-Year-Old Bridge
Refurbished on Route 20
A good-sized portion of a two-year, $6.6 million, rehabilitation
project of a 71-year-old, 415 foot bridge, spanning 18 Mile
Creek in Evans, New York was successfully completed recently
with the help of Concrete Cutting & Breaking, Inc. - Lancaster,
New York.
CCB was awarded this job based on their
past history with Oakgrove Construction, as well as for their
reputation for large scale projects that require solid planning
and methods.
Over thirteen thousand vehicles cross the
bridge each day, a traffic load that definitely played a role
in the deterioration of the bridge deck. In addition, the
age of the bridge itself contributed to its weakened state.
The aggressive project included deck replacement,
concrete repairs to the arch ribs, piers and abutments, new
architectural panels, coating of all exposed concrete at completion
of the work and reconstruction of the immediate roadway approaches.
The concrete cutting portion of this job included 96 pillar
arch cuts and 26 beam cuts so that the architectural integrity
of the bridge could be maintained.
The first half of the project was scheduled
to begin at the center span of the bridge where the deck and
floorbeams were to be removed so that the columns and arches
could be exposed. Repairs, if needed, were to be made and
then the bridge deck installed.
Prior to cutting, a working platform was
constructed and placed approximately 2 feet below the pier
cuts. The first cutting performed was the vertical beam cuts.
This required two saws cutting simultaneously between each
pier as a crane held each beam with just enough tension from
above. The job required the cutting to be done from both sides
of each beam.
On each beam removal, a #11 reinforcement
bar was left uncut to prevent the piece of concrete from moving
and slamming the blades; the rebar was torched after the cutting
was completed. The beam was then lifted by the crane and lowered
to the ground 90 feet below. CCB then mounted the wall saws
on the arches. This cutting also required that each arch be
double cut and held in place by the crane, due to excessive
pressure and movement in the bridge structure. The final cutting
was the horizontal pier cuts, also requiring saw cuts from
both sides and the crane providing tension to prevent the
blades from slamming.
As the large concrete sections of the bridge
were removed, they had to be immediately replaced with the
new, keeping the same weight load and structural integrity
of the bridge at all times. The prevented cracking of the
existing bridge structure that was to remain.
A large quantity of structural concrete
had to be removed in a short period of time. Access also proved
to be quite difficult as the bridge stands 90 feet above the
creek. The bottom portions of the bridge could not be damaged
during the job, nor could debris fall into the water or creek
bed below. In addition, one large crane was used instead of
multiple pieces of equipment, so the planning for the removal
phase of the project had to take this into consideration.
Today, thanks to CCB, thousands of cars
once again flow across this historic bridge.
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