News staff writer
Black drift fences and one backhoe parked on a hill are
among the signs that construction work is imminent for Interstate 84 near
Exit 44 in Cascade Locks.
Wildish Standard Paving, of Eugene, has begun
preparatory work for a multi-year project to repair and replace bridges
along the highway in Hood River County.
That includes replacing two bridges and repairing five
between Cascade Locks and Hood River. The work is expected to last through
Nov. 2010. Most of it will be invisible to passers-by as it will take
place out of sight under the freeway.
But the most visible phase will be the first, which
involves the replacement bridge near Exit 44 in Cascade Locks. Interstate
84 crosses a bridge over Highway 30, where it accesses both the freeway
and Frontage Road near the weigh station.
The first step will be to build a detour bridge, which
is expected to begin in three weeks. The next steps involve demolishing
the old bridges, one at a time, and rebuilding new ones.
The Oregon Department of Transportation is spending
$1.3 billion on the statewide bridge improvements, which it has contracted
out to another agency. Jason Ruth is the construction coordinator for the
contractor, Oregon Bridge Delivery Partners.
“The reason why we’re repairing and replacing bridges
is due to increased freight loads Oregon is seeing,” he said.
Those freight loads come primarily from trucks. As
weight passes over bridges, pressure transfers downward. Bridges sustain
weight first through a concrete deck, then by girders to crossbeams to
columns and finally the ground.
During inspections of Oregon bridges in 2001, engineers
found diagonal-tension cracks indicating bridges needed reinforcing to
handle the strain. In 2003, the state legislature passed the Oregon
Transportation Investment Act III, a $2.46-billion package that includes
the $1.3 billion to fix bridges.
Preliminary work at Cascade Locks to relocate a utility
under the bridge that crosses Highway 30 has been completed and
contractors have installed silt fences to prevent erosion. Signs have also
been erected for traffic control; although Ruth emphasized that traffic
isn’t expected to be delayed but only slowed down by the work.
“There will be very temporary impacts for shifting
traffic,” he said.
“There will be a couple of periods when we need to
close the highway when we demolish the old bridges and set the concrete
girders.”
Ruth said OBDP is working with the Cascade Locks port
of entry weigh station to minimize impacts on trucks coming from
Washington to weigh in and also heading through eastbound.
The five repair bridges include Frontage Road (Second
Street) bridge over Union Pacific Railroad, eastbound I-84 over the
railroad at milepost 47.3, Interstate 84 over Herman Creek Connector and
Interstate 84 at milepost 47.3 and over Moody Street at milepost 43.9.
Among the other repairs are plans to strengthen
concrete through various methods of pressurizing it. Ruth said the
analysis at Moody Street, for example, showed that the crossbeams needed
strengthening. To add support to the existing concrete, workers will be
drilling a hole through the cross beam and inserting a steel rod into the
beam.
“They then pull on the rod, which pushes on the
concrete and gives more resistance,” Ruth said.
“It’s known as post-tensioning.”
At Moody Street, workers will also be putting in steel
bars and sealing with epoxy.
For more information and up-to-date traffic details, visit
www.tripcheck.com
