NHI 130091 – Fracture Critical Inspection
Techniques Exam: Verified Questions and
Answers | Instant PDF Study Guide
1. What is the primary purpose of a fracture-critical
inspection?
A. To determine the age of a bridge
B. To estimate the bridge's remaining service life
C. To identify defects or deterioration that could lead to
catastrophic failure of a fracture-critical member
D. To verify the bridge's posted load rating
Rationale: A fracture-critical inspection is specifically intended
to identify conditions that could initiate or propagate a failure in
a member whose fracture or failure could result in the loss of
the bridge or a major portion of it. The inspection therefore
emphasizes critical members, connections, welds, details, and
areas susceptible to fatigue and fracture.
2. Which characteristic best defines a fracture-critical
member?
A. A member carrying only live load
B. A member that is difficult to access
C. A member whose failure could cause a portion or the entire
bridge to collapse
D. A member fabricated exclusively from high-strength steel
,Rationale: A fracture-critical member is one for which failure
would have serious structural consequences because there is
insufficient redundancy to safely redistribute the load.
Accessibility, material strength, and loading type alone do not
determine whether a member is fracture critical.
3. Which type of structural redundancy is most directly
associated with fracture-critical behavior?
A. Architectural redundancy
B. Inspection redundancy
C. Load-path redundancy
D. Maintenance redundancy
Rationale: Load-path redundancy refers to the existence of
multiple independent ways for loads to reach the supports.
When a critical member is the only practical load path, its
failure can result in collapse, making redundancy a fundamental
consideration in fracture-critical inspection.
4. During a fracture-critical inspection, why are fatigue-prone
details given particular attention?
A. Fatigue damage always produces large visible deformations
B. Fatigue cracks occur only in concrete members
C. Fatigue cracks can initiate and grow under repeated loading
and may eventually cause sudden fracture
D. Fatigue is eliminated when a bridge is painted
,Rationale: Repeated traffic loading can produce fatigue cracks
at stress concentrations, welds, connections, holes, and other
details. A crack may remain relatively small and difficult to
detect while progressively reducing the member's ability to
carry load.
5. Which inspection method is generally most appropriate for
detecting a surface-breaking crack that is not readily
visible?
A. Visual inspection alone
B. Dye penetrant testing
C. Concrete rebound testing
D. Ultrasonic thickness measurement only
Rationale: Dye penetrant testing can reveal surface-breaking
discontinuities by allowing penetrant to enter the opening and
subsequently become visible during development. It is
particularly useful for detecting fine surface cracks on suitable
nonporous surfaces.
6. What is the principal advantage of magnetic particle
testing?
A. It measures member temperature
B. It determines concrete compressive strength
C. It can detect surface and near-surface discontinuities in
ferromagnetic materials
D. It measures the remaining thickness of steel
, Rationale: Magnetic particle testing uses a magnetic field and
ferromagnetic particles to reveal discontinuities that disturb the
magnetic field. It is effective for detecting surface and shallow
subsurface cracks in appropriate ferromagnetic steels.
7. Which nondestructive testing method is commonly used to
locate internal discontinuities in steel members?
A. Visual inspection
B. Dye penetrant testing
C. Ultrasonic testing
D. Hammer sounding of concrete
Rationale: Ultrasonic testing introduces high-frequency sound
waves into a material and analyzes reflected signals. This allows
inspectors to identify discontinuities located below the surface,
including certain internal cracks and laminations.
8. What is a major limitation of visual inspection for fracture-
critical members?
A. It cannot identify corrosion
B. It cannot be performed in the field
C. Very small, tight, subsurface, or obscured cracks may not be
visible
D. It requires specialized electronic equipment for every
observation
Techniques Exam: Verified Questions and
Answers | Instant PDF Study Guide
1. What is the primary purpose of a fracture-critical
inspection?
A. To determine the age of a bridge
B. To estimate the bridge's remaining service life
C. To identify defects or deterioration that could lead to
catastrophic failure of a fracture-critical member
D. To verify the bridge's posted load rating
Rationale: A fracture-critical inspection is specifically intended
to identify conditions that could initiate or propagate a failure in
a member whose fracture or failure could result in the loss of
the bridge or a major portion of it. The inspection therefore
emphasizes critical members, connections, welds, details, and
areas susceptible to fatigue and fracture.
2. Which characteristic best defines a fracture-critical
member?
A. A member carrying only live load
B. A member that is difficult to access
C. A member whose failure could cause a portion or the entire
bridge to collapse
D. A member fabricated exclusively from high-strength steel
,Rationale: A fracture-critical member is one for which failure
would have serious structural consequences because there is
insufficient redundancy to safely redistribute the load.
Accessibility, material strength, and loading type alone do not
determine whether a member is fracture critical.
3. Which type of structural redundancy is most directly
associated with fracture-critical behavior?
A. Architectural redundancy
B. Inspection redundancy
C. Load-path redundancy
D. Maintenance redundancy
Rationale: Load-path redundancy refers to the existence of
multiple independent ways for loads to reach the supports.
When a critical member is the only practical load path, its
failure can result in collapse, making redundancy a fundamental
consideration in fracture-critical inspection.
4. During a fracture-critical inspection, why are fatigue-prone
details given particular attention?
A. Fatigue damage always produces large visible deformations
B. Fatigue cracks occur only in concrete members
C. Fatigue cracks can initiate and grow under repeated loading
and may eventually cause sudden fracture
D. Fatigue is eliminated when a bridge is painted
,Rationale: Repeated traffic loading can produce fatigue cracks
at stress concentrations, welds, connections, holes, and other
details. A crack may remain relatively small and difficult to
detect while progressively reducing the member's ability to
carry load.
5. Which inspection method is generally most appropriate for
detecting a surface-breaking crack that is not readily
visible?
A. Visual inspection alone
B. Dye penetrant testing
C. Concrete rebound testing
D. Ultrasonic thickness measurement only
Rationale: Dye penetrant testing can reveal surface-breaking
discontinuities by allowing penetrant to enter the opening and
subsequently become visible during development. It is
particularly useful for detecting fine surface cracks on suitable
nonporous surfaces.
6. What is the principal advantage of magnetic particle
testing?
A. It measures member temperature
B. It determines concrete compressive strength
C. It can detect surface and near-surface discontinuities in
ferromagnetic materials
D. It measures the remaining thickness of steel
, Rationale: Magnetic particle testing uses a magnetic field and
ferromagnetic particles to reveal discontinuities that disturb the
magnetic field. It is effective for detecting surface and shallow
subsurface cracks in appropriate ferromagnetic steels.
7. Which nondestructive testing method is commonly used to
locate internal discontinuities in steel members?
A. Visual inspection
B. Dye penetrant testing
C. Ultrasonic testing
D. Hammer sounding of concrete
Rationale: Ultrasonic testing introduces high-frequency sound
waves into a material and analyzes reflected signals. This allows
inspectors to identify discontinuities located below the surface,
including certain internal cracks and laminations.
8. What is a major limitation of visual inspection for fracture-
critical members?
A. It cannot identify corrosion
B. It cannot be performed in the field
C. Very small, tight, subsurface, or obscured cracks may not be
visible
D. It requires specialized electronic equipment for every
observation
