Part 8

Question 1

What is a one way concrete slab?

Answer 1

A one way concrete slab is a type of slab with reinforcement only in one direction, cast integrally w parallel supporting beams

Question 2

True or False: One way concrete slabs are generally used for short spans.

Answer 2

True

Question 3

What type of loads do one way concrete slabs primarily resist?

Answer 3

Bending loads

Question 4

What is the minimum thickness recommended for one way concrete slabs?

Answer 4

100mm
span/30 for floor slabs
span/36 for roof slabs

Question 5

What is the typical spacing of reinforcement bars in one way concrete slabs?

Answer 5

100mm to 200mm

Question 6

Why are one way concrete slabs not suitable for longer spans?

Answer 6

Due to potential deflection issues.

Question 7

What is the recommended concrete mix for one way concrete slabs?

Answer 7

25MPa

Question 8

What is the main advantage of using one way concrete slabs?

Answer 8

They are cost-effective and easy to construct.

Question 9

What is the maximum span length recommended for one way concrete slabs?

Answer 9

6m

Question 10

True or False: One way concrete slabs can be used in areas with heavy traffic loads.

Answer 10

False

Question 11

What type of reinforcement is commonly used in one way concrete slabs?

Answer 11

Steel reinforcement

Question 12

One way concrete slabs are designed as ____________ slabs.

Answer 12

simply supported, on two sides by beams or load bearing walls. Beams can be supported by girders or columns

Question 13

True or False: One way concrete slabs are suitable for irregularly shaped structures.

Answer 13

False

Question 14

What is the primary disadvantage of one way concrete slabs?

Answer 14

Limited span length capabilities.

Question 15

What is the critical design aspect to consider when designing one way concrete slabs?

Answer 15

Reinforcement spacing and arrangement.

Question 16

True or False: One way concrete slabs are suitable for heavy industrial structures.

Answer 16

False

Question 17

What is the recommended depth of one way concrete slabs for residential construction?

Answer 17

100mm

Question 18

What is a floor system?

Answer 18

Horizontal plane supporting live loads (people furnishings, movable equipment) and dead loads (weight of floor construction) - depth related to size and proportion of structural bay span + material strength. Deflection is a critical control factor. Consider mech and elec within the system. Consider sound and FRR.

Question 19

What is the purpose of a vapour barrier in Canada?

Answer 19

To prevent moisture from entering the building envelope.

Question 20

True or False: In Canada, vapour barriers are required by the building code.

Answer 20

True

Question 21

What type of material is commonly used for vapour barriers in Canada?

Answer 21

Polyethylene plastic

Question 22

What is the recommended placement of a vapour barrier in Canada?

Answer 22

On the warm side of the insulation

Question 23

Fill in the blank: Vapour barriers in Canada are typically installed on the __________ side of the building envelope.

Answer 23

warm

Question 24

What can happen if a vapour barrier is installed on the cold side of the insulation?

Answer 24

Moisture can get trapped and cause damage.

Question 25

What is the main function of a vapour barrier in Canada?

Answer 25

To control the movement of moisture vapor.

Question 26

What are some consequences of not installing a vapour barrier in Canada?

Answer 26

Mold growth, rot, and reduced energy efficiency.

Question 27

Fill in the blank: Vapour barriers are designed to prevent the diffusion of __________ through the building envelope.

Answer 27

moisture

Question 28

What are some common locations for installing vapour barriers in Canada?

Answer 28

Walls, ceilings, and floors

Question 29

What is the recommended perm rating for a vapour barrier in Canada?

Answer 29

Less than 1 perm

Question 30

What is the purpose of a vapour barrier in a Canadian building during the winter?

Answer 30

To prevent warm indoor air from condensing on cold surfaces.

Question 31

What are some potential benefits of installing a vapour barrier in a Canadian building?

Answer 31

Improved energy efficiency, increased comfort, and reduced risk of moisture damage.

Question 32

Fill in the blank: Vapour barriers are designed to be a __________ barrier to prevent moisture from entering the building envelope.

Answer 32

continuous

Question 33

Two way slab and beam

Answer 33

Uniform thickness reinforced in 2 directions, cast integrally w supporting beams and columns on all 4 sides (square ish bays = most efficient). Reinforcement in column and middle strips. Subject to lower bending moments than simply supported slabs.

Question 34

Two way waffle slab

Answer 34

2 way concrete reinforced by ribs in 2 directions - able to carry heavier loads and longer spans. At column heads, solid squares are used for additional shear strength and momentum resisting capacity. Can be cantilevered 1/3 of the main span.

Question 35

Two way flat plate

Answer 35

Uniform thickness over columns without beams - good for apartment or hotel construction. Shear at column locations governs thickness of flat plate. Shear at column main consideration.

Question 36

Two way flat plate

Answer 36

Uniform thickness over columns without beams - good for apartment or hotel construction. Shear at column locations governs thickness of flat plate. Shear at column main consideration.

Question 37

Two way flat slab

Answer 37

Flat plate thickened at column supports to increase shear strength and moment resisting capacity. Can support relatively heavy loads and spans from 6-12m

Question 38

Pretensioning

Answer 38

Stretched reinforced tendons into concrete casting - tensile tension causes slight upward curvature or camber - deflection of member under loading tends to equalize the curvature

Question 39

Tensioning reinforcing tendons after concrete has set

Answer 39

Post tensioning

Question 40

What is the span range for a 2x6

Answer 40

Up to 10’ (3050mm)

Question 41

Span range for a 2x8

Answer 41

8-12’ (2440-3660”

Question 42

Span range for 2x10

Answer 42

10-14’ (3050 - 4264mm)

Question 43

Span range for 2x12

Answer 43

12-18’ (3660-5485)

Question 44

True or false: stiffness of joist framing under stress is more important than strength

Answer 44

True - deeper joists spaced farther apart are more desirable for stiffness than shallow joists spaced close together