NHI 2-WEEK BRIDGE INSPECTION
TRAINING EXAM #1 QUESTIONS
AND ANSWERS
Creep - ANSWER-Gradual, continuing deformation due to constant stress below
yield strength.
Fatigue - ANSWER-Tendency to fail at stress below yield stress when subject to
cyclical loading.
Rolled 'I' beam - ANSWER-flanges and web 1 piece, <36" deep, compact section (no
stiffener needed).
Build-up I beam - ANSWER-larger shape, welded=new bridges, rivets=older bridges.
Physical Properties: Steel - ANSWER-Resists impact & vibration, 0.1%-2.1% carbon
and various yield strength.
Mechanical Properties: Steel - ANSWER-Isotropic=high comp. & tens. strength,
elastic, ductile; temperature, welding and fatigue prone failures, prone of corrosion if
unprotected, resist fatigue cracking (fracture toughness).
High performance steel - ANSWER-Improved weldability, high toughness, ductile
and corrosion resistance.
High Strength Bolt - ANSWER-A325 (92ksi yield & 120ksi tensile) and A490 (130ksi
yield & 150ksi tensile).
Physical Properties: Timber - ANSWER-hard = needles leaves, soft=loses leaves in
winter, growth features affect strength and increase moisture = decrease strength
and increase decay.
Mechanical Properties: Timber - ANSWER-Orthotropic, non-homo behavior, strength
varies depend on specie, resistance: fire, fatigue and impact, prone to creeping.
Deficiencies - Timber - ANSWER-Inherent defects, fungi, insects, marine borers and
in-service defects (collision, etc.)
Types of Steel deficiencies - ANSWER-Corrosion, fatigue cracking, overloads
(deformation), collision, heat damage and weathering steel failure.
Steel - location for inspection - ANSWER-Areas of high stress, water/debris trap,
problem details, traffic exposure and overall structure.
Physical Properties: Concrete - ANSWER-Thermal expansion, porous=flow of water,
volume changes due to moisture, fire resistance and formability.
TRAINING EXAM #1 QUESTIONS
AND ANSWERS
Creep - ANSWER-Gradual, continuing deformation due to constant stress below
yield strength.
Fatigue - ANSWER-Tendency to fail at stress below yield stress when subject to
cyclical loading.
Rolled 'I' beam - ANSWER-flanges and web 1 piece, <36" deep, compact section (no
stiffener needed).
Build-up I beam - ANSWER-larger shape, welded=new bridges, rivets=older bridges.
Physical Properties: Steel - ANSWER-Resists impact & vibration, 0.1%-2.1% carbon
and various yield strength.
Mechanical Properties: Steel - ANSWER-Isotropic=high comp. & tens. strength,
elastic, ductile; temperature, welding and fatigue prone failures, prone of corrosion if
unprotected, resist fatigue cracking (fracture toughness).
High performance steel - ANSWER-Improved weldability, high toughness, ductile
and corrosion resistance.
High Strength Bolt - ANSWER-A325 (92ksi yield & 120ksi tensile) and A490 (130ksi
yield & 150ksi tensile).
Physical Properties: Timber - ANSWER-hard = needles leaves, soft=loses leaves in
winter, growth features affect strength and increase moisture = decrease strength
and increase decay.
Mechanical Properties: Timber - ANSWER-Orthotropic, non-homo behavior, strength
varies depend on specie, resistance: fire, fatigue and impact, prone to creeping.
Deficiencies - Timber - ANSWER-Inherent defects, fungi, insects, marine borers and
in-service defects (collision, etc.)
Types of Steel deficiencies - ANSWER-Corrosion, fatigue cracking, overloads
(deformation), collision, heat damage and weathering steel failure.
Steel - location for inspection - ANSWER-Areas of high stress, water/debris trap,
problem details, traffic exposure and overall structure.
Physical Properties: Concrete - ANSWER-Thermal expansion, porous=flow of water,
volume changes due to moisture, fire resistance and formability.
