Concrete Stairs (2.0)

Question 1

definition of post tensioned

Answer 1

concrete tensioned after curing

Question 2

supported stairs are?

Answer 2

supported directly on the ground

Question 3

suspended stairs are?

Answer 3

supported by landings, columns and walls

Question 4

inverted stringers or cleats are attached to the?

Answer 4

side forms or walls

Question 5

inverted stringers or cleats should be kept a distance of at least?

Answer 5

30mm above the level of the treads

Question 6

rebar should be installed prior to the?

Answer 6

risers

Question 7

centre stringers or bracing should be used for stairs over?

Answer 7

1 metre in width

Question 8

when should form oil be applied?

Answer 8

before rebar is installed

Question 9

when is reshoring required?

Answer 9

before the concrete reaches its design strength

Question 10

When can stair forms be stripped?

Answer 10

5-7 days after the concrete’s been placed

Question 11

What are factors to be considered for exterior concrete stairs?

Answer 11

Existing grades, site conditions, end users

Question 12

Units of run tend to be larger for?

Answer 12

Exterior stairs instead of interior

Question 13

What should be done to avoid problems with settlement or heaving?

Answer 13

Exterior concrete stairs should be supported below the frost line by footings, grade beams, or piles

Question 14

Precast stairs for commercial are usually cast in?

Answer 14

Metal or fiberglass forms, and are pre-stressed

Question 15

What is a flight?

Answer 15

Uninterrupted section of stairs (platform to platform)

Question 16

When should a key or keyway be installed?

Answer 16

Where stairs are to be cast in a stairwell

Question 17

How are keyways formed?

Answer 17

Attaching a beveled piece of wood to the wall

Question 18

What does effective depth (throat) mean?

Answer 18

Smallest measurement between the throat and the soffit lines

Question 19

The throat must be?

Answer 19

Deep enough to provide proper concrete coverage above and below all reinforcing bars

Question 20

Plywood strips _ wide, provide sufficient strength for the stringer after notches are cut out.

Answer 20

300-400mm

Question 21

What is false work?

Answer 21

Framing members that brace and support stair forms

Question 22

Stairs used in high traffic areas may require?

Answer 22

Nosing protection to reduce wear and prevent chipping of the concrete

Question 23

To avoid water-related discolouration, architectural concrete forms must be?

Answer 23

Watertight

Question 24

What is the traditional unit rise for interior stairs?

Answer 24

180mm (7”)

Question 25

What is the unit rise as low as for locations used by the public?

Answer 25

140mm (5 1/2") ## Footnote Often specified.

Question 26

What is the minimum concrete cover required for rebar in most structural applications?

Answer 26

1"

Question 27

What is a structure that resists mostly vertical loads called?

Answer 27

A column

Question 28

What is a beam that is supported at both ends called?

Answer 28

Simple beam

Question 29

How long does concrete take to reach desired strength?

Answer 29

28 days

Question 30

What is the typical compressive strength of unreinforced concrete?

Answer 30

6,000 psi

Question 31

What are closed stairs?

Answer 31

Located between walls

Question 32

What are open stairs?

Answer 32

Open on both sides or open on one side only with a wall on the other side.

Question 33

What are residential stairs reinforced with?

Answer 33

Wire mesh.

Question 34

What is the maximum vertical distance specified between landings?

Answer 34

3700mm (12').

Question 35

Where are reinforcing bars bent and embedded?

Answer 35

Into the key way.

Question 36

Where are handrails used?

Answer 36

On closed stairs.

Question 37

Where are guards used?

Answer 37

On open stairs.

Question 38

What is the throat?

Answer 38

Effective depth.

Question 39

Stepping off should be limited to?

Answer 39

Stairs of six risers or less, or stairs that do not have a fixed total rise or run.

Question 40

What is the more accurate choice for laying out concrete stringers?

Answer 40

Layout rod

Question 41

What degree should the bottom edge be bevelled?

Answer 41

30-40 degrees

Question 42

Stairs built on grade should be built directly on?

Answer 42

Hard compacted soil

Question 43

Between uses, patterned architectural concrete form liners must be?

Answer 43

Carefully cleaned

Question 44

Stairs and landings are usually cast at the?

Answer 44

Same time

Question 45

What's the most common choice for riser material?

Answer 45

38mm solid stock lumber

Question 46

Why is the bottom edge of the risers form bevelled?

Answer 46

To allow concrete finishers to float and trowel the tread surface back to the riser while forms are still in place