WATER MAIN INSTALLATION AND
BACKFILLING EXAM QUESTIONS AND
ANSWERS GRADED A+ 2025/2026
What is the angle of repose ? - ANS For a given excavation in a specific soil it's the angle in
which the surrounding soil will not slide in or cave into the trench.
What is bedding ? - ANS Material placed in the trench to create suitable foundation for the
pipe.
What is cohesive soil ? - ANS Soil that contains lots of clay
What is frost haven ? - ANS The expansion of frozen soil that can cause damage to water
mains.
What is restraint fittings ? - ANS Fittings that prevent pipe movement in places where thrust
blocks is not an option.
What is shoring ? - ANS A framework that maintain pressure against both sides of a trench
wall.
1 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
, What is sloping ? - ANS A method preventing trench cave in by angling the sides of the trench
and relying on the soil's cohesive strength to prevent cave in.
What is sheeting ? - ANS A process where tightly spaced vertical planks are placed to form a
solid barrier against the trench walls to prevent cave in.
What is shielding ? - ANS A steel framed box that is open at the top and bottom and at the
ends used to protect workers from trench cave in.
What is spoil ? - ANS Soil excavated from the trench
What is a thrust block ? - ANS A large mass of concrete that is installed between the fitting
being restrained and the undisturbed soil that surrounds it.
What is a thrust anchor ? - ANS Steel rods anchored in large masses of concrete that are
attached to the pipe or fitting that is being restrained.
What is a tie rod ? - ANS A variation of the restraining fitting that is used to restrain
mechanical joint fittings when a thrust block cannot be used due to obstruction.
4 steps in pipe installation - ANS Inspect pipe
Unload pipe
Properly stack the pipe
Stringing (lay out the pipe)
When should a pipe be inspected ? - ANS As it is unloaded to check for damage that may
have occurred from shipments and that it's the proper size.
2 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
BACKFILLING EXAM QUESTIONS AND
ANSWERS GRADED A+ 2025/2026
What is the angle of repose ? - ANS For a given excavation in a specific soil it's the angle in
which the surrounding soil will not slide in or cave into the trench.
What is bedding ? - ANS Material placed in the trench to create suitable foundation for the
pipe.
What is cohesive soil ? - ANS Soil that contains lots of clay
What is frost haven ? - ANS The expansion of frozen soil that can cause damage to water
mains.
What is restraint fittings ? - ANS Fittings that prevent pipe movement in places where thrust
blocks is not an option.
What is shoring ? - ANS A framework that maintain pressure against both sides of a trench
wall.
1 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
, What is sloping ? - ANS A method preventing trench cave in by angling the sides of the trench
and relying on the soil's cohesive strength to prevent cave in.
What is sheeting ? - ANS A process where tightly spaced vertical planks are placed to form a
solid barrier against the trench walls to prevent cave in.
What is shielding ? - ANS A steel framed box that is open at the top and bottom and at the
ends used to protect workers from trench cave in.
What is spoil ? - ANS Soil excavated from the trench
What is a thrust block ? - ANS A large mass of concrete that is installed between the fitting
being restrained and the undisturbed soil that surrounds it.
What is a thrust anchor ? - ANS Steel rods anchored in large masses of concrete that are
attached to the pipe or fitting that is being restrained.
What is a tie rod ? - ANS A variation of the restraining fitting that is used to restrain
mechanical joint fittings when a thrust block cannot be used due to obstruction.
4 steps in pipe installation - ANS Inspect pipe
Unload pipe
Properly stack the pipe
Stringing (lay out the pipe)
When should a pipe be inspected ? - ANS As it is unloaded to check for damage that may
have occurred from shipments and that it's the proper size.
2 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
