ACI Concrete Strength Testing Technician CP-19 (14)
100% CORRECT ANSWERS
These procedures for capping enable concrete cylinders and cores to meet the standard's
requirements for ________ and _________. correct answers Planeness, perpendicularity
Equipment needed for the capping process includes capping _____ , _____devices, and
______ pots. correct answers Plates, alignment, melting
Plates for neat cement and high strength gypsum plaster caps should be made of _____,
_____, _____ or _____. correct answers Glass, metal granite or diabase
Sulfur mortar cap plates should be formed against _____ or _____ plates. correct answers
Metal, Stone
The purpose of the guide bar or bull's eye level is to ensure that caps remain perpendicular to
the axis of the cylinder within 0.5 degrees. True or False? correct answers True
To avoid accidents during reheating of cooled sulfur, use melting pots that have _____.
correct answers Peripheral heating
The technician should use a stiff layer of _____ to cap fresh concrete cylinders. correct
answers Neat cement paste
Hardened concrete cylinders should be capped with _____, _____ or _____. correct answers
High-strength gypsum paste, neat cement paste, or sulfur mortar
Plaster of paris and mixtures of plaster of paris and portland cement are examples of suitable
high strength plasters. True or False? correct answers False
Sulfur mortars and high-strength gypsum cement cubes must demonstrate a minimum
compressive strength of _____ or ___ __, whichever is greater. correct answers 35MPa (5000
psi), the cylinder strength
The cement paste should be applied to the freshly molded cylinder from _____ to _____
hours after molding. This is to allow for _____ of the concrete specimen. correct answers 2,4,
settling
The strength of the paste depends on:
a) the water-cement ratio
b) time
c) the equipment used
d) type of cement correct answers a, b and d
A slight twisting action will help eliminate _____ and air _____ when the capping plate is
placed onto the mound of the paste. correct answers Excess paste, voids
Neat cement paste caps should not be used on dry specimens because the caps may _____
and _____ when dry. correct answers Shrink, crack
, The technician should remove all _____ or _____ materials from the ends of hardened
concrete cylinders before capping correct answers Oily, waxy
_____ the pot and recharge with fresh material at intervals to insure that the oldest material in
the pot has not been used more than _____ times. correct answers Empty, 5
When capping concrete cylinders with a compressive strength of 35 MPa (5000 psi) or
greater, it is permitted to reuse compound recovered from the capping operation of old caps.
True or False? correct answers False
To avoid _____, the sulfur mortar should be dry when it is added to the pot. It should be kept
away from _____ when heating. correct answers Foaming, water
The melting pot for the sulfur mortar must be located under a _____ with an _____ for
_____. correct answers Hood, exhaust fan, ventillation
Hydrogen sulfide gas, which may be produced during capping, may be _____, _____, _____,
_____ and _____. correct answers Lethal, nausea, stomach distress, dizziness, headache,
irritation of the eyes.
When qualification tests of unbonded pads are required, they are performed by the _____ or
_____. correct answers Supplier, user
This standard (ASTM 1231) established a maximum number of pad reuses that may not be
exceeded under any circumstances. True or false? correct answers False
Unbonded caps are not to be used for acceptance testing of concrete with compressive
strength below _____ or above _____. correct answers 1500 psi (10 MPa), 12,000 psi (80
MPa)
Polyurethane or butyl pads with a Shore A durometer hardness of 50 that will be used on
concrete with a compressive strength of 1500 to 6000 psi (10 to 40 MPa) need not be
qualified prior to use. True of False? correct answers False
To keep track of pad usage, the user is required to maintain records that include_____.
correct answers Date placed in service, pad durometer, number of uses
if a new neoprene pad with a Shore A durometer hardness of 50 is intended to test concrete
cylinders with anticipated compressive strengths between 1500 and 6000 psi (10 and 40
MPa), it may be used "as is" from the manufacturer without further qualification testing. True
or False? correct answers True
The term "unbonded cap" refers to the combination of a metal retainer and an elastomeric
pad. True or False? correct answers True
The practice of ASTM C1231 may be used instead of the capping requirements ASTM C617.
True or False? correct answers True
100% CORRECT ANSWERS
These procedures for capping enable concrete cylinders and cores to meet the standard's
requirements for ________ and _________. correct answers Planeness, perpendicularity
Equipment needed for the capping process includes capping _____ , _____devices, and
______ pots. correct answers Plates, alignment, melting
Plates for neat cement and high strength gypsum plaster caps should be made of _____,
_____, _____ or _____. correct answers Glass, metal granite or diabase
Sulfur mortar cap plates should be formed against _____ or _____ plates. correct answers
Metal, Stone
The purpose of the guide bar or bull's eye level is to ensure that caps remain perpendicular to
the axis of the cylinder within 0.5 degrees. True or False? correct answers True
To avoid accidents during reheating of cooled sulfur, use melting pots that have _____.
correct answers Peripheral heating
The technician should use a stiff layer of _____ to cap fresh concrete cylinders. correct
answers Neat cement paste
Hardened concrete cylinders should be capped with _____, _____ or _____. correct answers
High-strength gypsum paste, neat cement paste, or sulfur mortar
Plaster of paris and mixtures of plaster of paris and portland cement are examples of suitable
high strength plasters. True or False? correct answers False
Sulfur mortars and high-strength gypsum cement cubes must demonstrate a minimum
compressive strength of _____ or ___ __, whichever is greater. correct answers 35MPa (5000
psi), the cylinder strength
The cement paste should be applied to the freshly molded cylinder from _____ to _____
hours after molding. This is to allow for _____ of the concrete specimen. correct answers 2,4,
settling
The strength of the paste depends on:
a) the water-cement ratio
b) time
c) the equipment used
d) type of cement correct answers a, b and d
A slight twisting action will help eliminate _____ and air _____ when the capping plate is
placed onto the mound of the paste. correct answers Excess paste, voids
Neat cement paste caps should not be used on dry specimens because the caps may _____
and _____ when dry. correct answers Shrink, crack
, The technician should remove all _____ or _____ materials from the ends of hardened
concrete cylinders before capping correct answers Oily, waxy
_____ the pot and recharge with fresh material at intervals to insure that the oldest material in
the pot has not been used more than _____ times. correct answers Empty, 5
When capping concrete cylinders with a compressive strength of 35 MPa (5000 psi) or
greater, it is permitted to reuse compound recovered from the capping operation of old caps.
True or False? correct answers False
To avoid _____, the sulfur mortar should be dry when it is added to the pot. It should be kept
away from _____ when heating. correct answers Foaming, water
The melting pot for the sulfur mortar must be located under a _____ with an _____ for
_____. correct answers Hood, exhaust fan, ventillation
Hydrogen sulfide gas, which may be produced during capping, may be _____, _____, _____,
_____ and _____. correct answers Lethal, nausea, stomach distress, dizziness, headache,
irritation of the eyes.
When qualification tests of unbonded pads are required, they are performed by the _____ or
_____. correct answers Supplier, user
This standard (ASTM 1231) established a maximum number of pad reuses that may not be
exceeded under any circumstances. True or false? correct answers False
Unbonded caps are not to be used for acceptance testing of concrete with compressive
strength below _____ or above _____. correct answers 1500 psi (10 MPa), 12,000 psi (80
MPa)
Polyurethane or butyl pads with a Shore A durometer hardness of 50 that will be used on
concrete with a compressive strength of 1500 to 6000 psi (10 to 40 MPa) need not be
qualified prior to use. True of False? correct answers False
To keep track of pad usage, the user is required to maintain records that include_____.
correct answers Date placed in service, pad durometer, number of uses
if a new neoprene pad with a Shore A durometer hardness of 50 is intended to test concrete
cylinders with anticipated compressive strengths between 1500 and 6000 psi (10 and 40
MPa), it may be used "as is" from the manufacturer without further qualification testing. True
or False? correct answers True
The term "unbonded cap" refers to the combination of a metal retainer and an elastomeric
pad. True or False? correct answers True
The practice of ASTM C1231 may be used instead of the capping requirements ASTM C617.
True or False? correct answers True
