ACI Concrete Strength Testing
Technician Exam Review (25th Ed.)
These procedures for capping enable concrete cylinders and cores to meet the
standard practice's requirements for _____ and _____. - ANSWER-Planeness;
Perpendicularity
Equipment needed for the capping process includes capping _____, _____ devices,
and _____ pots. - ANSWER-Plates; alignment; melting
Plates for neat cement and high-strength gypsum plaster caps should be made of
_____, _____, _____, or _____. - ANSWER-Glass; Metal; Granite; Diabase
Sulfur mortar cap plates should be formed against _____ or _____ plates. - ANSWER-
Metal; Granite or diabase
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? - ANSWER-
True
To avoid accidents during the reheating of cooled sulfur, use melting pots that have
_____. - ANSWER-Peripheral Heating
Hardened concrete cylinders should be capped with _____,_____,_____, or _____. -
ANSWER-High-Strength gypsum paste; neat cement paste; sulfur mortar
Plaster of paris and mixtures of plaster of paris and portland cement are examples of
suitable high-strength plasters. True or False? - ANSWER-False
Sulfur mortars and high-strength gypsum cement cubes must demonstrate a minimum
compressive strength of _____ or _____, whichever is greater. - ANSWER-5000 psi
[35MPa]; Cylinder Strength
The cement paste should be applied to the freshly molded cylinder from _____ hours
after molding. This is to allow for _____ of the concrete speciment. - ANSWER-2 to 4;
settling
Select all that apply: The strength of the neat cement paste depends on:
A. The water-cement ratio
B. Curing Time/ Age of cap
C. The equipment used
, D. Type of Cement - ANSWER-A, B, D
The slight twisting action will help eliminate _____ and air _____ when capping plate is
placed onto the mound of neat cement paste. - ANSWER-Excess Paste, Voids
To keep track of pad usage, the user is required to maintain records that include _____,
_____, and ___ - ANSWER-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 cylinder with anticipated compressive strengths between 10 and 40 MPa [1500
and 6000 psi], it may be used "as is" from the manufacturer without further qualification
testing. True or False? - ANSWER-True
The term "unbonded cap" refers to the combination of a metal retainer and an
elastomeric pad. True or False? - ANSWER-True
Practice C1231/C1231M may be used instead of the capping requirements of Practice
C617/C617M. True or False? - ANSWER-True
The pads provide a uniform distribution of load from the bearing blocks of the testing
machine by deforming in initial loading to conform to the contour of the ends of the
cylinder. True or False? - ANSWER-True
When qualifying unbonded caps, strengths below _____ of the average obtained from
bonded caps is considered unacceptable. - ANSWER-98%
Practice C1231/C1231M contains step-by-step procedures for aligning the specimens in
the testing machine through complete failure of the cylinder. True or False? - ANSWER-
False
The pads used in this practice must be _____ thick, and the diameter shall not be more
than _____ smaller than the inside diameter of the retaining ring. - ANSWER-1/2 +- 1/16
in (leeway); 1/16 in
The height of the metal retaining ring must be. - ANSWER-1 in +- .10 in (leeway)
The inside diameter of the retaining rings shall not be less than _____ or greater than
_____ of the diameter of the cylinder. - ANSWER-102%; 107%
Depressions in the ends of the cylinder that exceed _____ must be corrected by sawing
or grinding prior to testing. - ANSWER-0.20 in
Qualification tests on an unbonded capping system must be repeated whenever there
are changes in. - ANSWER-The design or dimensions of the retaining rings; pad
composition or thickness; the Shore A hardness by more than five units.
Technician Exam Review (25th Ed.)
These procedures for capping enable concrete cylinders and cores to meet the
standard practice's requirements for _____ and _____. - ANSWER-Planeness;
Perpendicularity
Equipment needed for the capping process includes capping _____, _____ devices,
and _____ pots. - ANSWER-Plates; alignment; melting
Plates for neat cement and high-strength gypsum plaster caps should be made of
_____, _____, _____, or _____. - ANSWER-Glass; Metal; Granite; Diabase
Sulfur mortar cap plates should be formed against _____ or _____ plates. - ANSWER-
Metal; Granite or diabase
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? - ANSWER-
True
To avoid accidents during the reheating of cooled sulfur, use melting pots that have
_____. - ANSWER-Peripheral Heating
Hardened concrete cylinders should be capped with _____,_____,_____, or _____. -
ANSWER-High-Strength gypsum paste; neat cement paste; sulfur mortar
Plaster of paris and mixtures of plaster of paris and portland cement are examples of
suitable high-strength plasters. True or False? - ANSWER-False
Sulfur mortars and high-strength gypsum cement cubes must demonstrate a minimum
compressive strength of _____ or _____, whichever is greater. - ANSWER-5000 psi
[35MPa]; Cylinder Strength
The cement paste should be applied to the freshly molded cylinder from _____ hours
after molding. This is to allow for _____ of the concrete speciment. - ANSWER-2 to 4;
settling
Select all that apply: The strength of the neat cement paste depends on:
A. The water-cement ratio
B. Curing Time/ Age of cap
C. The equipment used
, D. Type of Cement - ANSWER-A, B, D
The slight twisting action will help eliminate _____ and air _____ when capping plate is
placed onto the mound of neat cement paste. - ANSWER-Excess Paste, Voids
To keep track of pad usage, the user is required to maintain records that include _____,
_____, and ___ - ANSWER-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 cylinder with anticipated compressive strengths between 10 and 40 MPa [1500
and 6000 psi], it may be used "as is" from the manufacturer without further qualification
testing. True or False? - ANSWER-True
The term "unbonded cap" refers to the combination of a metal retainer and an
elastomeric pad. True or False? - ANSWER-True
Practice C1231/C1231M may be used instead of the capping requirements of Practice
C617/C617M. True or False? - ANSWER-True
The pads provide a uniform distribution of load from the bearing blocks of the testing
machine by deforming in initial loading to conform to the contour of the ends of the
cylinder. True or False? - ANSWER-True
When qualifying unbonded caps, strengths below _____ of the average obtained from
bonded caps is considered unacceptable. - ANSWER-98%
Practice C1231/C1231M contains step-by-step procedures for aligning the specimens in
the testing machine through complete failure of the cylinder. True or False? - ANSWER-
False
The pads used in this practice must be _____ thick, and the diameter shall not be more
than _____ smaller than the inside diameter of the retaining ring. - ANSWER-1/2 +- 1/16
in (leeway); 1/16 in
The height of the metal retaining ring must be. - ANSWER-1 in +- .10 in (leeway)
The inside diameter of the retaining rings shall not be less than _____ or greater than
_____ of the diameter of the cylinder. - ANSWER-102%; 107%
Depressions in the ends of the cylinder that exceed _____ must be corrected by sawing
or grinding prior to testing. - ANSWER-0.20 in
Qualification tests on an unbonded capping system must be repeated whenever there
are changes in. - ANSWER-The design or dimensions of the retaining rings; pad
composition or thickness; the Shore A hardness by more than five units.
