NHI SAFETY LATEST
INSPECTION OF IN-
SERVICE BRIDGES
FINAL EXAM
Top 4 tests for small surface deficiencies in steel - ANSWERS-dye
penatrant
magnetic particle testing
eddy current
ultrasonic
top 4 tests for subsurface deficiencies - ANSWERS-ultrasonic
radiography
magnetic particle
eddy current
top 3 tests to evaluate internal cracks in truss pin - ANSWERS-
ultrasonic
phased array
radiography
END OF
PAGE
1
, NHI SAFETY LATEST
INSPECTION OF IN-
SERVICE BRIDGES
FINAL EXAM
electrical / half cell potential - ANSWERS-evaluates corrosion activity
of reinforcing steel in concrete
need exposed rebar
ground penetrating radar - ANSWERS-high frequency pulsed
electromagnetic waves to acquire subsurface info
can measure the thickness of asphalt covering
determines delaminations
pachometer - ANSWERS-magnetic device to determine the position of
reinforcement
determines in adequate coverage of concrete
impact echo test - ANSWERS-flaw detection in concrete
not effective for large areas
END OF
PAGE
2
, NHI SAFETY LATEST
INSPECTION OF IN-
SERVICE BRIDGES
FINAL EXAM
acoustic wave testing - ANSWERS-delineate areas of internal cracking
and deteriorated concrete
sonic testing - ANSWERS-detects decay and other low density regions
in timber
spectral analysis - ANSWERS-uses sonic waves to produce stress waves
in timber member
vibration testing - ANSWERS-checking vibrating frequency to
determine sound members
moisture meter - ANSWERS-determines moisture content in timber
members
field ohmmeter - ANSWERS-electrical resistance inside drilled hole to
detect decay
END OF
PAGE
3
, NHI SAFETY LATEST
INSPECTION OF IN-
SERVICE BRIDGES
FINAL EXAM
multi-beams - ANSWERS-rolled shapes
deck placed on top
30 to 50 feet spans
36 in to 44 inches
may have cover plates
multi-girder - ANSWERS-fabricated
larger than rolled beams
can span over 500 feet
riveted or welded
can utilize steel stiffer plates
two-girder - ANSWERS-similar to multi- girder
but has a floor system between girders
floor system supports deck
END OF
PAGE
4
INSPECTION OF IN-
SERVICE BRIDGES
FINAL EXAM
Top 4 tests for small surface deficiencies in steel - ANSWERS-dye
penatrant
magnetic particle testing
eddy current
ultrasonic
top 4 tests for subsurface deficiencies - ANSWERS-ultrasonic
radiography
magnetic particle
eddy current
top 3 tests to evaluate internal cracks in truss pin - ANSWERS-
ultrasonic
phased array
radiography
END OF
PAGE
1
, NHI SAFETY LATEST
INSPECTION OF IN-
SERVICE BRIDGES
FINAL EXAM
electrical / half cell potential - ANSWERS-evaluates corrosion activity
of reinforcing steel in concrete
need exposed rebar
ground penetrating radar - ANSWERS-high frequency pulsed
electromagnetic waves to acquire subsurface info
can measure the thickness of asphalt covering
determines delaminations
pachometer - ANSWERS-magnetic device to determine the position of
reinforcement
determines in adequate coverage of concrete
impact echo test - ANSWERS-flaw detection in concrete
not effective for large areas
END OF
PAGE
2
, NHI SAFETY LATEST
INSPECTION OF IN-
SERVICE BRIDGES
FINAL EXAM
acoustic wave testing - ANSWERS-delineate areas of internal cracking
and deteriorated concrete
sonic testing - ANSWERS-detects decay and other low density regions
in timber
spectral analysis - ANSWERS-uses sonic waves to produce stress waves
in timber member
vibration testing - ANSWERS-checking vibrating frequency to
determine sound members
moisture meter - ANSWERS-determines moisture content in timber
members
field ohmmeter - ANSWERS-electrical resistance inside drilled hole to
detect decay
END OF
PAGE
3
, NHI SAFETY LATEST
INSPECTION OF IN-
SERVICE BRIDGES
FINAL EXAM
multi-beams - ANSWERS-rolled shapes
deck placed on top
30 to 50 feet spans
36 in to 44 inches
may have cover plates
multi-girder - ANSWERS-fabricated
larger than rolled beams
can span over 500 feet
riveted or welded
can utilize steel stiffer plates
two-girder - ANSWERS-similar to multi- girder
but has a floor system between girders
floor system supports deck
END OF
PAGE
4
