BCGBC4010A Apply structural principles to residential low-rise constructions

Floor systems

Topic activity
Question 1 of 22
Which concrete slab construction has no stiffening beam?
A.	Slab on ground
B.	Waffle raft slab
C.	Stiffened raft slab
D.	Infill slab
The correct answer is D - Infill slab. It is cast in ground between walls and with no stiffening beam.

Question 2 of 22
During the scraping process, how much of the top layer is removed?
A.	50 - 100 mm
B.	150 - 200 mm
C.	100 - 150 mm
D.	200 - 250 mm
The correct answer is C - 100 - 150 mm. This is enough to remove and grass or organic matter.

Question 3 of 22
Which of the following factors does not help calculate the excavation depth of beams?
A.	Depth of vegetation
B.	Width of slab
C.	Allowable bearing soil below surface
D.	Height of slab
The correct answer is B - Width of slab.

Question 4 of 22
Edge rebates need to be provided in the edge stiffening beams if external walls are going to be of what type?
A.	Brick veneer and full masonry
B.	Full masonry only
C.	Timber
D.	Block only
The correct answer is A - Brick veneer and full masonry. It creates a ledge for both types of masonry to rest on.

Question 5 of 22
Is additional reinforcement needed if pipes are laid under the slab?
A.	Yes
B.	No
The correct answer is A - Yes. This it to avoid weakening of the slab.

Question 6 of 22
Does slab thickness have to be increased if hot water pipes are embedded in the slab?
A.	Yes
B.	No
The correct answer is A - Yes. Slab thickness is increased by 25 mm and the mesh size is also increased.

Question 7 of 22
Is a moisture barrier a plastic membrane laid under a slab?
A.	Yes
B.	No
The correct answer is A - Yes. The moisture barrier is placed under the slab to help prevent rising damp.

Question 8 of 22
What does the term 4-L11TM mean when designated to trench bars? 
A.	11 bars, 4 mm in diameter
B.	4 bars, 4 mm in diameter
C.	11 bars, 11 mm in diameter
D.	4 bars, 11 mm in diameter
The correct answer is D - 4 bars, 11 mm in diameter. The first number relates to the number of bars and the last to the diameter in mm.

Question 9 of 22
What does the term SL82 mean when designated to square mesh?
A.	8 mm diameter bars on a grid 200 mm apart
B.	82 diameter bars on a grid 20 mm apart
C.	2 mm diameter bars on a grid 80 mm apart
D.	2 mm diameter bars on a grid 200 mm apart
The correct answer is A - 8 mm diameter bars on a grid 200 mm apart. The first digit relates to the diameter of the bar and the second to the spacing of bars.

Question 10 of 22
What is the diameter of a reinforcing bar designated N12?
A.	1 m
B.	1 mm
C.	12 mm
D.	12 m
The correct answer is C - 12 mm. The number after the letter refers to the diameter of the bar in mm.

Question 11 of 22
On what type of sites can slabs on ground be constructed?
A.	Class A and Class S sites
B.	All sites
C.	Class M and Class H sites
D.	Class S and Class P sites
The correct answer is A - Class A and Class S sites. These are rock, sand and sightly reactive clay sites.

Question 12 of 22
What is the most common and easiest slab to construct?
A.	Slab on ground
B.	Footing slab 
C.	Stiffened raft slab
D.	Waffle raft slab
The correct answer is C - Stiffened raft slab. It can be laid on all sites except 
Class P.

Question 13 of 22
Which of the following footing slabs is most suited to sloping sites?
A.	Remote from site
B.	Connection between slab and footing
C.	No connection between slab and footing
D.	None of the above
The correct answer is A - Remove from site. But only on Class A and Class S sites.

Question 14 of 22
Footings on which sites must be designed by an engineer?
A.	Class A and Class S sites
B.	Class E and Class S sites
C.	Class E and Class P sites
D.	Class P sites only
The correct answer is C - Class E and Class P sites. Class E is extremely reactive clay and Class P is a problem site.

Question 15 of 22
For ventilation what is the minimum ground clearance from the underside of the beam to FGL?
A.	200 mm
B.	150 mm
C.	100 mm
D.	250 mm

The correct answer is B - 150 mm. It might need to be even greater if termite inspection is required.

Question 16 of 22
What does FLW refer to?
A.	Footing load width
B.	Floor load width
C.	Force load of wind
D.	Footing length width
The correct answer is B - Floor load width. This needs to be known to calculate the bearer size.

Question 17 of 22
What spans can joists be?
A.	Single span only
B.	Continuous span only
C.	Double span
D.	Single and continuous span
The correct answer is D - Single and continuous span. This is the same for bearers.

Question 18 of 22
Which of these is not a joist joint?
A.	Dovetail joint 
B.	Scarf joint
C.	Butt joint
D.	Timber cleat
The correct answer is A - Dovetail joint. This is a typical bearer joint.

Question 19 of 22
Which of these relates to deep floor joists?
A.	The height exceeds the width four times
B.	The width exceeds the height four times
C.	The height exceeds the width twice
D.	The width exceeds the height twice

The correct answer is A - The height exceeds the width four times. Also, it must be restrained from rolling over.

Question 20 of 22
What is the minimum length required for boards in fitted floors?
A.	The equivalent of one joist spacing
B.	The equivalent of five joist spacings
C.	The equivalent of two joist spacings
D.	None of the above
The correct answer is C - The equivalent of two joist spacings. These specifications are listed in AS 2796.

Question 21 of 22
Expansion joints are needed on floors that have a continuous width of what measurement?
A.	Over 6 m
B.	Over 10 m
C.	Over 6 mm
D.	Over 10 mm
The correct answer is A - Over 6 m. These are needed in addition to perimeter gaps.

Question 22 of 22
Which of the following is correct?
A.	Only machine-driven nails need to be punched.
B.	Only hand-driven nails need to be punched.
C.	All nails need to be punched.
D.	Only nails at butt joints need to be punched.
The correct answer is C - All nails need to be punched. This is necessary for sanding and finishing.

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