Use
of Fiber Reinforced Polymer (FRP) Reinforcement Cage in Concrete
Bridge Decking
Research
by
David A. Jacobson, Jr. & Mack
Conachen/
Prof.
Lawrence Bank, Prof.
Michael Oliva
& Prof. Jeff Russell
Dept of Civil & Environmental Engineering
The
deteriorating condition of bridges and other infrastructure
facilities is recognized by highway agencies as one of the most
complex problems in transportation infrastructure. As a result,
the Wisconsin Department of Transportation is seeking innovative
and cost-effective technologies to retrofit and rehabilitate
many of the State's bridges. Fiber reinforced polymer (FRP)
composites are becoming increasingly accepted as viable materials
for use in highway bridge construction due to their high strength
and stiffness to weight ratio and corrosion resistance. Bridge
decking is one promising application for FRP composites, as
it is expected to reduce construction times, bridge maintenance,
and overall life-cycle costs of bridges.
Research
at the University of Wisconsin Madison is being conducted to
investigate the use of an innovative, modular three-dimensional
FRP pultruded grid reinforcement system to construct a concrete
bridge deck on a major bridge structure. The project is part
of a new bridge structure on US Highway 151 over De Neveu Creek,
near the Wisconsin city of Fond du Lac. The two lane northbound
bridge, utilizes the FRP reinforcement system, and has a single
130-foot span with a width of roughly 45 feet. For purpose of
comparison, the bridge?s southbound counterpart has been constructed
with a conventional steel reinforced deck.
Recently,
the UW has developed an efficient and structurally adequate
FRP 
reinforcement
cage design for research purposes. The following items have
been investigated: strength and stiffness of the FRP reinforced
deck in flexure under simulated wheel loads, fatigue behavior
and residual strength during/after simulated cyclic wheel loading,
failure modes from fatigue and static loadings, and the general
constructibility/performance of a FRP deck reinforcement system.
With
these tests complete the Wisconsin Department of Transportation
accepted the FRP system for use in the Fond du Lac bridge. The
University of Wisconsin provided a quality assurance program
to provide a secondary verification of the material properties
used in the design of the bridge. The UW also preformed a constructibility
analysis of the bridge that included, site observation and cost
analysis of the project. This was done in order to determine
if the savings in field labor offset the extra cost of the material.
Photo:
Placement of super-sized grids
with the use of a crane
Additionally,
a load test of the bridges was preformed in conjunction with
the University of Missouri Rolla. This testing was to provide
a benchmark for future performance testing of the bridge by
the University of Marquette.
Photo:
View of FRP bridge during the load testing conducted by University
of Wisconsin and University of Missouri
The
implementation of FRP in Wisconsin bridge structures is in its
infancy; UW research is aimed at fostering its growth as a feasible
and possibly advantageous alternative to traditional bridge
construction materials. Lessons learned from this project could
lead to further use of this innovative system in other bridges
throughout the state.
