Concrete - Practice

Question 1

Concrete has a high strength of what type?

Answer 1

compressive strength

Question 2

How is the strength of concrete often compromised on the jobsite?

Answer 2

water is added

Question 3

How many cubic feet are in one cubic yard of concrete?

Answer 3

27 cubic feet

Question 4

How many cubic meters are there in one cubic foot?

Answer 4

.028 meters

Question 5

How many cubic metres of concrete would be required for 12 columns 2.4 metres high and 300 mm in diameter?

Answer 5

2.04

Question 6

How many cubic yards of concrete are necessary for a wall 10 inches thick, 8 feet high and 38 feet long?

Answer 6

9.38 cubic yards

Question 7

In areas where frost occurs, where must footings be placed?

Answer 7

below the frost line

Question 8

Once water has been added to the mix, how many minutes does a cement truck have to reach the job site?

Answer 8

maximum 90 minutes

Question 9

Pre-stressing of concrete members is for what purpose?

Answer 9

to counteract tensile stresses

Question 10

What are the two methods of pre-stressing concrete called?

Answer 10

pre-tensioning and post-tensioning

Question 11

What determines the pressure on concrete forms?

Answer 11

height and weight of concrete

Question 12

What do aggregates serve as?

Answer 12

fillers in concrete

Question 13

What do the letters ICF stand for?

Answer 13

insulated concrete forms

Question 14

What does the abbreviation WWM represent?

Answer 14

welded wire mesh

Question 15

What is a by-product of the curing of concrete?

Answer 15

heat

Question 16

What is a combined slab and foundation called?

Answer 16

monolithic slab

Question 17

What is an advantage of air-entrained Portland cement?

Answer 17

it resists freezing and thawing better

Question 18

What is concrete called when steel bars are used to increase concrete’s tensile strength?

Answer 18

reinforced concrete

Question 19

What is concrete made of?

Answer 19

Portland cement, aggregate, and water

Question 20

What is done to break off snap ties?

Answer 20

they are twisted one-quarter to one-half of a full turn

Question 21

What is done to provide a lock between the footing and the foundation?

Answer 21

a keyway is formed

Question 22

What is done with precast concrete panels for a watertight seal?

Answer 22

caulking

Question 23

What is necessary to prevent window and door bucks from deflecting under the load imposed by plastic concrete?

Answer 23

internal bracing and blocking

Question 24

What is the amount of water in relation to the amount of Portland cement called?

Answer 24

water-cement ratio

Question 25

What is the average time required for concrete to gain 90 percent of its full strength?

Answer 25

1 month

Question 26

What is the correct term for putting concrete into forms?

Answer 26

placing

Question 27

What is the curing process of concrete called?

Answer 27

hydration

Question 28

What is the diameter of #3 rebar?

Answer 28

3/8" (9.5 mm)

Question 29

What is the first step in finishing concrete flatwork?

Answer 29

striking-off

Question 30

What is the name for the forms that are used for providing large openings in a concrete wall?

Answer 30

bucks

Question 31

What is the name for the recesses in the top of a masonry wall to receive the ends of girders?

Answer 31

pockets

Question 32

What is the name for vertical thickened portions of a concrete wall that give the wall more lateral strength?

Answer 32

pilasters

Question 33

What is the name of the process that eliminates honeycomb?

Answer 33

consolidation

Question 34

What is the name of the test done on the jobsite to test the consistency of concrete?

Answer 34

slump test

Question 35

What is the name of vertical framing members placed at right angles to walers?

Answer 35

strongbacks

Question 36

What is the purpose of the water in concrete?

Answer 36

to begin the hydration process

Question 37

What is the typical strength range for concrete?

Answer 37

15 to 32 MPa

Question 38

What is the weight of a standard bag of Portland cement?

Answer 38

40 kg

Question 39

What is used when testing concrete for consistency?

Answer 39

a cone

Question 40

What must be done to the bottom edge of concrete stair form riser boards?

Answer 40

they must be bevelled to allow for finishing

Question 41

What type of footing is constructed on sloped ground?

Answer 41

stepped footing

Question 42

What type of insulation is used for ICFs?

Answer 42

extruded polystyrene

Question 43

When a concrete slab is placed directly on the ground, what is it commonly called?

Answer 43

slab-on-grade

Question 44

When are mat foundations used?

Answer 44

when soil is unstable

Question 45

When concrete is thickened under a load-bearing wall, what is it called?

Answer 45

haunched

Question 46

When should anchor bolts be placed?

Answer 46

as soon as the wall is screeded

Question 47

Where do snap ties break off?

Answer 47

at the outside face of the form panels

Question 48

Which aggregate size produces the strongest concrete?

Answer 48

19 mm (3/4")

Question 49

Which concrete construction type uses embeds?

Answer 49

tilt-up

Question 50

Which forming system uses steel waler bars?

Answer 50

strip-ease