QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED
ANSWERS) ALREADY GRADED A+.
Lightweight concrete is BEST used at the:
A. curb & gutter
B. second floor decking
C. first floor slab on grade
D. footings - ANSWER-B.
Second floor decking.
It is costly, but very strong. It offers greatest advantage when used for
upper stories because it reduces the strength requirements for the
supporting framework.
What tool do you normally use for striking joints?
A. haulk
B. trowel
C. jointer or jointing tool
D. stiff brush - ANSWER-B.
A trowel is normally used for striking joints.
What is a bush-hammer used for?
A. install bushings on a wheel
B. roughen surfaces of hardened concrete
C. straighten metai sheeting
D. pull objects with impact action - ANSWER-B.
Roughen the surface of hardened concrete.
,It is a hardened steel tool with a serrated face or several rows of
pyramid-shaped points. It is used to roughen the surface of hardened
concrete to provide better bonding of fresh concrete poured over it.
Who decides if 3,000 psi strength concrete is fit to pour?
A. structural engineer
B. supplier
C. concrete contractor
D. building inspector - ANSWER-A.
Structural engineer.
psi = pounds per square inch
Concrete should be poured against:
A any wood siding
B. cedar or redwood siding only
C. metal flashing
D. metal form material - ANSWER-D.
Metal form material.
When metal forms are not used, only "Form Grade" plywood, not
siding, should be used in the wood forms.
How soon should you pour concrete after you have mixed
it without additives?
A. 1/2 hour
B. 1 hour
C. 4 hours
D. 8 hours - ANSWER-A.
,1/2 hour.
You should begin placing concrete within 30 minutes of mixing, and it
MUST be placed within 90 minutes to prevent the concrete from
becoming too stiff and difficult to place and finish.
In cold climates, you cover freshly poured concrete to:
A. prevent hydration
B. prevent discoloration
C. prevent warping
D. prevent freezing - ANSWER-D.
Prevent freezing.
In order to hold in the heat, long enough for curing.
When should you trowel concrete?
A. when just poured
B. 1 hour after pouring
C. when concrete becomes firm, several hours after pour
D. after 24 hours - ANSWER-C.
You should trowel concrete several hours after pour when concrete
becomes firm.
A vapor barrier might not be needed between wood and concrete:
A. if the concrete is older than one year
B. with a moisture-proof sealer on the wood
C. A and B
D. neither A nor B, it will always be needed - ANSWER-C. A and B
, How many cubic yards of cement are required for a circle 4in thick,
with a circumference of 10ft?
A. 1/10 yd3
B. 1/5 yd3
C. 1/2 yd3
D. 1 yd3 - ANSWER-A.
1/10 yd3
Volume = area x thickness
Area of a circle = pr2 r =
circumference + 2p r = 10
+ 2p p=3.14 r= 10 + 6.28
=1.59 ft Area of a circle =
pr2
Area:::: p (1.59)2 == 3.14 x 1.59 x 1.59 Area== 7.94
Volume = area x thickness
4" + 12" per foot == 0.33333' Volume== 7.94 x 0.33:::: 2.62 ft3 Conver
to yards
2.62 + 27 =::.097 yd3
Round to 0.10 yd or 1/10
What is the correct procedure when drilling concrete?
A. use steady, medium pressure
B. periodically pull back to let dust escape
C. A&B
D. concrete should never be drillled - ANSWER-C. A&B
What is the MINIMUM size for anchor bolts?