CONCRETE TEST ALL POSSIBLE QUESTIONS AND
ANSWERS 2023 WITH COMPLETE SOLUTION
What is the minimum required thickness for a slab?
3 1/2"
What is the max spacing of the anchor bolts for a 1-story house?
6' o. c.
What is the max spacing of the anchor bolts for a 2-story house?
4' o. c.
Minimum width of footing for 1-story house
12"
Minimum width of footing for 2-story house
15"
Anchor bolts must be embedded _____ into a slab
7"
What is the minimum size anchor bolt that can be used in SEISMIC CATEGORY D?
#4 or 1/2"
What is the minimum size anchor bolts that can be used in SEISMIC CATEGORY E?
#5 or 5/8"
What's the purpose of rebar?
To increase the tensile strength of concrete
What is the purpose of deformed rebar?
To improve the bond between steel and concrete
The main field of a slab must be reinforced by a ___________ grid
18"x18"
The sides of the main field of the slab must be reinforced with a ________ grid
15"x18"
What size rebar is used to reinforce a stem wall?
#4 or 1/2". Same as a concrete slab
What's the maximum spacing of rebar in a stem wall?
18"
The concrete stem walls must have #4 rebar ____ from the top of the footing as well as
____ from the bottom of the footing.
3" from top and 3" from bottom
What's the spacing of anchor bolts from ends of sill plates?
4" min - 12" max
What is minimum depth of a footing below the soil?
12"
What size is #3 rebar?
3/8"
What class of formwork is used for temporary or light loads?
Class I.
Class II is for structures requiring heavy loads
What size of footing is required for a 2-story building with a load bearing value of 1500
psf?
, 15
The highest load bearing value substrate is?
Bedrock
What's the standard overlap for a #4 rebar?
It is 30x the size of the rebar. #4 rebar is 1/2" so 30 times 1/2" is 15"
To ensure proper grounding, the grounding electrode must be encased by how many
inches of concrete?
-must be encased by 2" or more of concrete
-electrode must be at or near the bottom of the footing or foundation
-concrete must be in contact with the ground
-at least 20' of rebar that is at least 1/2" thick or 20' of solid copper as a conductor
Control joints in sidewalks should be spaced at what intervals?
Generally the control joints in sidewalks should be spaced equal to the width of the slab
but not more than 6 ft apart.
What's the max spacing of control joints in driveways?
20 ft. The control joints should be spaced equal to the width of the slab.
What's the max spacing of the control joints in a slab that is to receive a floor finish such
as carpet or hardwood?
Control joints aren't necessary in this scenario because unsightly cracks will be covered
by flooring
What will cause concrete to lose its strength?
Too much water
What is the ideal temperature for curing concrete?
75F. The range is between 50F and 85F
What is the minimum mixing time for a mixture of 1 cubic yard?
1 minute of mixing for mixtures of 1 cubic yard
What is a construction joint?
Joints designed to separate one pour from another
What type concrete would be used for quick dry applications?
Type 3
One cubic foot of cement weighs approximately?
95 lbs
When batching concrete, what percentage of concrete powder is commonly used?
25% to 40% cement powder
At what times during setup, is it important to pay special attention to keeping concrete
sufficiently moist?
In hot and cold weather. Cold weather reduces air humidity while hot weather increases
evaporation
A mix with a higher percentage of rock has the advantage of?
Being less expensive
Air-entraining
Improves the working life of concrete
Max strength of concrete is reached after?
28 days
Finishing with a steel float?
Reduces risk of cracking
ANSWERS 2023 WITH COMPLETE SOLUTION
What is the minimum required thickness for a slab?
3 1/2"
What is the max spacing of the anchor bolts for a 1-story house?
6' o. c.
What is the max spacing of the anchor bolts for a 2-story house?
4' o. c.
Minimum width of footing for 1-story house
12"
Minimum width of footing for 2-story house
15"
Anchor bolts must be embedded _____ into a slab
7"
What is the minimum size anchor bolt that can be used in SEISMIC CATEGORY D?
#4 or 1/2"
What is the minimum size anchor bolts that can be used in SEISMIC CATEGORY E?
#5 or 5/8"
What's the purpose of rebar?
To increase the tensile strength of concrete
What is the purpose of deformed rebar?
To improve the bond between steel and concrete
The main field of a slab must be reinforced by a ___________ grid
18"x18"
The sides of the main field of the slab must be reinforced with a ________ grid
15"x18"
What size rebar is used to reinforce a stem wall?
#4 or 1/2". Same as a concrete slab
What's the maximum spacing of rebar in a stem wall?
18"
The concrete stem walls must have #4 rebar ____ from the top of the footing as well as
____ from the bottom of the footing.
3" from top and 3" from bottom
What's the spacing of anchor bolts from ends of sill plates?
4" min - 12" max
What is minimum depth of a footing below the soil?
12"
What size is #3 rebar?
3/8"
What class of formwork is used for temporary or light loads?
Class I.
Class II is for structures requiring heavy loads
What size of footing is required for a 2-story building with a load bearing value of 1500
psf?
, 15
The highest load bearing value substrate is?
Bedrock
What's the standard overlap for a #4 rebar?
It is 30x the size of the rebar. #4 rebar is 1/2" so 30 times 1/2" is 15"
To ensure proper grounding, the grounding electrode must be encased by how many
inches of concrete?
-must be encased by 2" or more of concrete
-electrode must be at or near the bottom of the footing or foundation
-concrete must be in contact with the ground
-at least 20' of rebar that is at least 1/2" thick or 20' of solid copper as a conductor
Control joints in sidewalks should be spaced at what intervals?
Generally the control joints in sidewalks should be spaced equal to the width of the slab
but not more than 6 ft apart.
What's the max spacing of control joints in driveways?
20 ft. The control joints should be spaced equal to the width of the slab.
What's the max spacing of the control joints in a slab that is to receive a floor finish such
as carpet or hardwood?
Control joints aren't necessary in this scenario because unsightly cracks will be covered
by flooring
What will cause concrete to lose its strength?
Too much water
What is the ideal temperature for curing concrete?
75F. The range is between 50F and 85F
What is the minimum mixing time for a mixture of 1 cubic yard?
1 minute of mixing for mixtures of 1 cubic yard
What is a construction joint?
Joints designed to separate one pour from another
What type concrete would be used for quick dry applications?
Type 3
One cubic foot of cement weighs approximately?
95 lbs
When batching concrete, what percentage of concrete powder is commonly used?
25% to 40% cement powder
At what times during setup, is it important to pay special attention to keeping concrete
sufficiently moist?
In hot and cold weather. Cold weather reduces air humidity while hot weather increases
evaporation
A mix with a higher percentage of rock has the advantage of?
Being less expensive
Air-entraining
Improves the working life of concrete
Max strength of concrete is reached after?
28 days
Finishing with a steel float?
Reduces risk of cracking
