CSLB Concrete C8 License Practice Test #1 | 87QUESTIONS WITH
ANSWERS LATEST UPDATED 100% VERIFIED SOLUTIONS (
ALREADY GRADED A+)
What is the volume of a cylinder if the diameter equals 3 feet and the length equals to 12 feet? -
(answer)84.78 cubic feet
Explanation:
There are two ways to solve the problem. However, regardless of which method is used, you
need to first determine the area of the circle then multiply it by the length.Traditional MethodUse
the following formula:Area of the circle = π x r x rWhere π = 3.14 and radius (r) = 1.5 feet (half
of the diameter length)Area = 3.14 x 1.5 x 1.5Area = 7.065 sq. ft.Multiply area by the length to
find the volume.7.065 x 12 = 84.78Shortcut MethodArea of the circle is 78.5% of the square.
Treat the circle as a square and solve for the area.Find the area of the square instead of the
circle.3' x 3' = 9 sq. ft.Since circle is 78.5% of the square, multiply area of the square by 78.5%
(or .785 if there is no percentage sign on the calculator).9 sq. ft. x .785 = 7.065 square
feetMultiply area by the length to find the volume.7.065 x 12 = 84.78 cubic feet
Where are spiral rebar ties used? - (answer)In round columns
Control joints in sidewalks should be spaced at what intervals? - (answer)Equal to the width of
the slab
Explanation:
Generally the control joints in sidewalks should be spaced equal to the width of the slab, but not
more than 6 feet apart.
One cubic foot of cement weighs approximately: - (answer)95 lbs
How many cubic yard of concrete is required for a 4" slab with the diameter of 15 feet? -
(answer)2 ½ cubic yards
,Explanation:
Traditional MethodUse the following formula:Area of the circle = π x r x rWhere π = 3.14 and
radius (r) = 7.5 feet (half of the diameter length)Area = 3.14 x 7.5 x 7.5Area = 176.625 sq.
ft.Multiply area by the depth of the slab (in feet) to find the volume in cubic feet.176.625 x .333
= 58.82 cubic feetConvert cubic feet into cubic yards.58.82 ÷ 27 = 2.18 cubic yardsSince 2.18 is
not a given option, round up the number to 2.5 cubic yardsShortcut MethodThis problem can be
solved using a much simpler method. First is to find the area of the square, then convert it into
the area of the circle by multiplying it by 78.5%.Area of the square = 15' x 15' = 225 square
feetArea of the circle = 225 x .785 = 176.625 square feetDivide the volume by 81 to solve for the
cubic yards for a 4" slab.176.625 ÷ 81 = 2.18 cubic yardsSince 2.18 is not a given option, round
up the number to 2.5 cubic yards
The normal tolerance for the location of bends and ends of reinforcing bar is: - (answer)+/- 2
inches
How many cubic yards of backfill are required for a 3' x 5' trench, 1500 ft long, with a 1 foot
diameter pipe? - (answer)789.72
Explanation:
Step 1. Find the net face area of the trench deducting for pipe.Face area including pipe: 3 x 5 =
15 square feetArea of the pipe: 𝐴=𝜋𝑟2A = 3.14 x .5 x .5A = 0.785Find the face area of the trench
minus area of the pipe, which will give you the net area for the backfill.15 - 0.785 = 14.215Step
2. Find the total volume of the backfill.14.215 x 1500 = 21322.5 cubic feetConvert the volume
into cubic yards.21322.5 ÷ 27 = 789.72 cubic yards
When can the live load be calculated by multiplying the height, width and length of a pour and
dividing by the deadload? - (answer)Never
Tensile strength in concrete is achieved by: - (answer)The use of steel reinforcement.
Refer to the house plan. What is the total cost for the foundation slab if the contractor charges
$3.54 per square foot? - (answer)$6524.90
, Explanation:
The easiest way to solve for the area of the slab is to image a full rectangle of the slab and
subtract void areas from the area of the slab.
Rectangle area: 28.167' x 71.5'= 2013.94 sq ftLeft void area: 6.667' x 1.83' = 12.2 sq ftCenter
void area: 11.5' x 1.83' = 21.045 sq ftRight void area: 9.167' x 15' = 137.505Net area of the
foundation slab: 2013.94 - 12.2 - 21.045 - 137.505 = 1843.19 sq ft.Calculate the price of the
slab.1843.19 sq ft x $3.54 = $6524.90
What is the minimum spacing of parallel reinforcing bars placed in two or more layers? -
(answer)1 inch
Explanation:
According to the American Concrete Institute, where parallel reinforcement is placed in two or
more layers, bars in the upper layers shall be placed directly above bars in the bottom layer with
clear distance between layers not less than 1 inch.
When applying concrete to concrete there are several factors to consider. Which is most
important? - (answer)In most cases the most important is the bond.
What is the purpose of the rebar? - (answer)To increase the tensile strength
There are many ornamental uses of concrete, including casting architectural elements,
ornaments, and faux finishes. How would you describe terrazzo in the simplest terms? -
(answer)A special combination of colored rock and glass for floors.
What is the minimum size of anchor bolt can be used in seismic category E? - (answer)#5
The building code requires 5/8" anchor bolt to be used in seismic category E.
ANSWERS LATEST UPDATED 100% VERIFIED SOLUTIONS (
ALREADY GRADED A+)
What is the volume of a cylinder if the diameter equals 3 feet and the length equals to 12 feet? -
(answer)84.78 cubic feet
Explanation:
There are two ways to solve the problem. However, regardless of which method is used, you
need to first determine the area of the circle then multiply it by the length.Traditional MethodUse
the following formula:Area of the circle = π x r x rWhere π = 3.14 and radius (r) = 1.5 feet (half
of the diameter length)Area = 3.14 x 1.5 x 1.5Area = 7.065 sq. ft.Multiply area by the length to
find the volume.7.065 x 12 = 84.78Shortcut MethodArea of the circle is 78.5% of the square.
Treat the circle as a square and solve for the area.Find the area of the square instead of the
circle.3' x 3' = 9 sq. ft.Since circle is 78.5% of the square, multiply area of the square by 78.5%
(or .785 if there is no percentage sign on the calculator).9 sq. ft. x .785 = 7.065 square
feetMultiply area by the length to find the volume.7.065 x 12 = 84.78 cubic feet
Where are spiral rebar ties used? - (answer)In round columns
Control joints in sidewalks should be spaced at what intervals? - (answer)Equal to the width of
the slab
Explanation:
Generally the control joints in sidewalks should be spaced equal to the width of the slab, but not
more than 6 feet apart.
One cubic foot of cement weighs approximately: - (answer)95 lbs
How many cubic yard of concrete is required for a 4" slab with the diameter of 15 feet? -
(answer)2 ½ cubic yards
,Explanation:
Traditional MethodUse the following formula:Area of the circle = π x r x rWhere π = 3.14 and
radius (r) = 7.5 feet (half of the diameter length)Area = 3.14 x 7.5 x 7.5Area = 176.625 sq.
ft.Multiply area by the depth of the slab (in feet) to find the volume in cubic feet.176.625 x .333
= 58.82 cubic feetConvert cubic feet into cubic yards.58.82 ÷ 27 = 2.18 cubic yardsSince 2.18 is
not a given option, round up the number to 2.5 cubic yardsShortcut MethodThis problem can be
solved using a much simpler method. First is to find the area of the square, then convert it into
the area of the circle by multiplying it by 78.5%.Area of the square = 15' x 15' = 225 square
feetArea of the circle = 225 x .785 = 176.625 square feetDivide the volume by 81 to solve for the
cubic yards for a 4" slab.176.625 ÷ 81 = 2.18 cubic yardsSince 2.18 is not a given option, round
up the number to 2.5 cubic yards
The normal tolerance for the location of bends and ends of reinforcing bar is: - (answer)+/- 2
inches
How many cubic yards of backfill are required for a 3' x 5' trench, 1500 ft long, with a 1 foot
diameter pipe? - (answer)789.72
Explanation:
Step 1. Find the net face area of the trench deducting for pipe.Face area including pipe: 3 x 5 =
15 square feetArea of the pipe: 𝐴=𝜋𝑟2A = 3.14 x .5 x .5A = 0.785Find the face area of the trench
minus area of the pipe, which will give you the net area for the backfill.15 - 0.785 = 14.215Step
2. Find the total volume of the backfill.14.215 x 1500 = 21322.5 cubic feetConvert the volume
into cubic yards.21322.5 ÷ 27 = 789.72 cubic yards
When can the live load be calculated by multiplying the height, width and length of a pour and
dividing by the deadload? - (answer)Never
Tensile strength in concrete is achieved by: - (answer)The use of steel reinforcement.
Refer to the house plan. What is the total cost for the foundation slab if the contractor charges
$3.54 per square foot? - (answer)$6524.90
, Explanation:
The easiest way to solve for the area of the slab is to image a full rectangle of the slab and
subtract void areas from the area of the slab.
Rectangle area: 28.167' x 71.5'= 2013.94 sq ftLeft void area: 6.667' x 1.83' = 12.2 sq ftCenter
void area: 11.5' x 1.83' = 21.045 sq ftRight void area: 9.167' x 15' = 137.505Net area of the
foundation slab: 2013.94 - 12.2 - 21.045 - 137.505 = 1843.19 sq ft.Calculate the price of the
slab.1843.19 sq ft x $3.54 = $6524.90
What is the minimum spacing of parallel reinforcing bars placed in two or more layers? -
(answer)1 inch
Explanation:
According to the American Concrete Institute, where parallel reinforcement is placed in two or
more layers, bars in the upper layers shall be placed directly above bars in the bottom layer with
clear distance between layers not less than 1 inch.
When applying concrete to concrete there are several factors to consider. Which is most
important? - (answer)In most cases the most important is the bond.
What is the purpose of the rebar? - (answer)To increase the tensile strength
There are many ornamental uses of concrete, including casting architectural elements,
ornaments, and faux finishes. How would you describe terrazzo in the simplest terms? -
(answer)A special combination of colored rock and glass for floors.
What is the minimum size of anchor bolt can be used in seismic category E? - (answer)#5
The building code requires 5/8" anchor bolt to be used in seismic category E.
