The experimental
Bridge Street Bridge “Structure B” will undergo a 5-year load test on
Thursday, December 7 beginning at 10 a.m. at the project site, located
on the north side of Eight Mile Road (M-102) just west of Telegraph
Road (US-24).
The experimental
bridge is one of two parallel bridges the City constructed over the
Rouge River to replace a failed bridge at the only access point to the
Bridge Street Industrial Park. The first new bridge, completed in May
2001, was constructed using standard concrete beams containing
conventional steel reinforcement. The second bridge, “Structure B”, was
built with 12 double tee (DT) concrete beams reinforced with carbon
fiber-reinforced polymer (CFRP) components − the first vehicular bridge
in the country to use this new technology. Because CFRP does not rust
like conventional steel, it is hoped that the success of this project
will eventually lead to widespread use of CFRP in the construction of
new and replacement bridges. The initial cost of a CFRP reinforced
bridge is presently significantly more expensive than steel; however,
the life of CFRP bridges is expected to be more than double that of
conventional bridges. Additionally, the cost of long-term maintenance
of composite material reinforced bridges is expected to be minimal
compared to that of conventional steel and concrete structures. Serious
bridge safety issues, such as chunks of concrete breaking off of
freeway bridges and falling onto traffic below, could also become a
thing of the past with the use of composites as bridge reinforcement.
The bridge is the
result of a collaborative effort between the city of Southfield, the
Federal Highway Administration (FHWA), the Michigan Department of
Transportation (MDOT), Lawrence Technological University (LTU) and
engineering consultants Hubbell, Roth & Clark (HRC), Inc. of
Bloomfield Hills, Michigan. The load test of “Structure B” will
duplicate an identical test performed on the bridge shortly after it
was completed in November of 2001. Engineers and technicians from
Construction Technology Laboratories, Inc. of Skokie, Illinois will
conduct instrument readings and hard data collection in conjunction
with the City Engineering Department and staff from LTU and HRC. As a
result of the test, one lane of both inbound and outbound traffic will
be shifted over to the east bridge (Structure A) while the west
composite bridge (Structure B) is closed from approximately 9 a.m. – 3
p.m.
For further information, contact Southfield City Engineer Wayne Bonus, at (248) 796-4816.