| ABSTRACT: | EXPERIMENTAL NON-DESTRUCTIVE TESTING OF FRP MATERIALS, INSTALLATION,
AND PERFORMANCE, DALLAS COUNTY BRIDGE, MISSOURI, USA
N. Maerz, G. Galecki, and A. Nanni
University Of Missouri-rolla, Rolla, MO, United States
An FRP (Fiber Reinforced Polymer) retrofit of a county bridge in Missouri provided the opportunity to use
new and existing technologies to test the FRP materials installations, and performance. Four different
technologies were investigated; concrete substrate surface roughness, FRP fiber alignment, FRP
delamination, and FRP bond pull-off strength. Results of testing to date are presented, and long term
monitoring plans will be given.
Surface substrate roughness of sand blasted surfaces were made, on selected locations of the bridge
abutments and bents, as well as the bridge deck, using a newly developed laser profilometer. The roughness
measurements are compared to the “idealized surface roughness”, and compared against any future
delamination, from pull-off tests and natural delamination.
FRP fiber alignment measurements were made using an imaging techniques that measures the angle between
control lines and special tracers embedded in the FRP materials.
FRP delamination testing was done using a specially modified impact echo tester, on production surfaces
and on surfaces with artificially created delaminations. All test sites are referenced with respect to
previously determined substrate roughness measurements. Tests will be done every 6 months for the next 5
years.
FRP bond pulloff strength testing was done using a specially designed pulloff tester. Testing was done to a
working load, pulloff failure is anticipated only for defective materials or installation. Pulloff plugs were
installed on selected locations on the bridge and referenced to roughness measurements. Testing will be
done every 6 months for the next 5 years.
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