CIVIL TECHNOLOGY: CIVIL SERVICES
GRADE 12
NATIONAL SENIOR CERTIFICATE
MEMORANDUM
SEPTEMBER 2018

QUESTION 1: SAFETY, MATERIAL AND EQUIPMENT (GENERIC)
1.1
1.1.1 True (1)
1.1.2 False (1)
1.1.3 False (1)
1.1.4 True (1)
1.2 Any THREE requirements to which a trestle scaffold must comply.

• Soundly constructed with a solid material
• Prevent spreading of supporting legs
• Not higher than 3 m
• Consists of not more than 2 tiers (3 x 1) (3)

1.3 Similar answer.
(1) Aluminium conducts (2) electricity / workers subjected to electrical shock (2)
1.4 Similar answer.
(1) Paint will cover (2) weaknesses (2)
1.5
1.5.2 Improves the durability of concrete. (1)
1.5.5 It improves the strength of concrete. (1)
1.5.7 It makes concrete more watertight. (1)
1.5.8 It improves the resistance to abrasion. (1)
1.6 (1) Plastic finish / coating (2) in powder form by (3) using a spray-gun (3)
1.7 Briefly describe any ONE use of the dumpy level.

• (1) Determine (2) height differences
• (1) Determine (2) levels and slopes
• (1) Setting out (2) of buildings
• (1) Transferring of (2) levels and heights
• (1) Determine horizontal (2) distances (1 x 2) (2)

1.8
1.8.1 1.5 m (1)
1.8.2 1.535 – 1,47 x 100 = 6,5 m (4)
1.9 Any THREE materials which can be detected in walls by the multi-detector.

• Ferrous metals
• Non-ferrous metals
• AC wiring
• Wood
• Metal studs
• Steel bars
• Copper pipes (3 x 1) (3)

1.10
1.10.1 Dry, soft cloth / Not cleaning agents or solvents (1)
1.10.2 Remove battery (1)
[30]

QUESTION 2: GRAPHICS AND JOINING (GENERIC)
2.1 Use the information on ANSWER SHEET A and complete the site plan on scale 1 : 200 according to the following requirements:
2.1.1 The site boundaries are measured from point A
The site boundaries in front and back are 23 m long
The site boundaries on the sides are 25 m long (2)
2.1.2 The front building line is 4 m from the site boundary
The back and side building lines are 2 m from the site boundaries (2)
2.1.3 Show the site entrance, 3 m from the western site boundary (1)
2.1.4 Show the datum level in the north-eastern corner of the site
Complete the sewage lay-out and abbreviations of the sewage appliances according to the following requirements: (1)
2.1.5 The main sewage from the bathroom to the municipal connection (2)
2.1.6 The branch sewage to the bathroom and kitchen (2)
2.1.7 Manhole on the site, before the municipal connection (2)
2.1.8 Rodding eyes (4)
2.1.9 Inspection eyes (4)
2.2

• Length of shank
• Diameter
• Type of thread
• Head size (4 x 1) (4)

2.3 (1) When square shoulder is driven in (2) it resists rotation (2)
2.4
2.4 A – Nut
2.4 B – Thread
2.4 C – Runout
2.4 D – Shank (4)
[30]
TOTAL: 60

QUESTION 3: SAFETY, MATERIAL, EQUIPMENT AND GRAPHICS (SPECIFIC)
3.1 Similar answer.
(1) Prevent (2) material / people / tools falling into the manhole (2)
3.2
3.2.1 Stairs (1)
3.2.2 Safety net (1)
3.2.3 Cover (1)
3.3 Any ONE responsibility of the contractor when working in elevated positions:

• (1) Appoint a competent person (2) responsible for the preparation (3) of a fall protective plan
• (1) Ensure that the protective plan (2) is implemented and (3) amended when necessary
• (1) Ensure that steps are taken (2) in order to adhere to (3) the fall protective plan (1 x 3) (3)

3.4 (1) When selectively removing zinc (2) from an alloy (2)
3.5 Any ONE consequence of dezincification when it occurs in an alloy:

• Leaves a porous metal
• -Leaves a metal with little mechanical strength (1)

3.6 White powder on the metal surface. (1)
3.7 Describe any TWO methods of preventing corrosion in metals:

• (1) Electrically (2) insulating the two metals
• (1) Make sure that there is no contact (2) with an electrolyte
• (1) Applying an antioxidant paste (2) to copper and aluminium surfaces
• (1) Choosing metals that (2) have similar electrode potentials
• (1) Connecting a DC current supply to (2) oppose the corrosive galvanic current (2 x 2) (4)

3.8
3.8.1 Drain cleaning rods (1)
3.8.2 Coil spring (1)
3.8.3 (1) Jet wash with (2) soapy water and (3) disinfectant (3)
3.9
3.9.1 Centrifugal pump (1)
3.9.2 Pipe-thread cutting machine (1)
3.9.3 Water pressure testing pump (1)
3.10 FIGURE 3.10 on ANSWER SHEET B shows a square-based truncated pyramid.
Draw on ANSWER SHEET B the pattern development for the pyramid. (16)
[40]

QUESTION 4: QUANTITIES AND JOINING (SPECIFIC)
4.1
4.1.1 Polycop (1)
4.1.2 1 3240 mm (13,24 m) (1)
4.1.3 Polycop (1)
4.1.4 8 800 mm (1,5 + 5,48 + 1,82 = 8,8 m) (1)
4.1.5 Copper (1)
4.1.6 1 (1)
4.1.7 Copper (1)
4.1.8 1 (1)
4.1.9 Copper (1)
4.1.10 1 (1)
4.1.11 Copper (1)
4.1.12 1 (1)
4.2
4.2.1 Branch pipe. (1) Pipe that branches off from (2) the main sewerage (2)
4.2.2 Cleaning eye. (1) Opening to (2) access the inside of a pipe (2)
4.2.3 Soil water. (1) Discharged from (2) water closet / Water that contains human waste (2)
4.3
4.3.1 Soil pipe – Green (1)
4.3.2 Soil-water vent pipe – Blue (1)
4.3.3 Existing sewerage – Black (1)
4.4
4.4.1 Pipe clip (1)
4.4.2 40 mm and 50 mm (2)
4.4.3 (1) To bind/fix polycop pipes (2) to surfaces (2)
4.5 = πr²h
= 22 x 1,05 x 1,05 x 2,4
    7
= 8,316 m³ (4)
4.6
4.6.1 True (1)
4.6.2 True (1)
4.6.3 False (1)
4.6.4 False (1)
4.7
4.7.1 Compression joint (1)
4.7.2
4.7.A – Compression rubber seal
4.7.B – Compression screw (2)
4.7.3 uPVC-pipes (1)
4.8 (1) Thin layer of tin / solder is (2) melted onto the tip of the soldering iron (2)
[40]

QUESTION 5: CONSTRUCTION, COLD-WATER AND HOT-WATER SUPPLY (SPECIFIC)
5.1 FIGURE 5.1 on ANSWER SHEET C shows layer 1 of a double return angle in a one-brick wall in stretcher bond. Draw in good ratio on ANSWER SHEET C the alternative layer for the brick wall. (6)
5.2 FIGURE 5.2 on ANSWER SHEET D shows the incomplete top view of a concrete manhole. Complete in good ratio the branch connection and pipe work in the manhole. (3)
5.3 Any TWO reasons why the concrete benching in a manhole is constructed at a slope:

• Sewer spills can backslide into channel pipe
• So that rats and other vermin cannot settle there (2 x 1) (2)

5.4 Any TWO positions where manholes must be installed:

• (1) Close as possible to municipal connection (2) but not further than 2 m from the boundary fence
• (1) Every 20–25 m on a (2) straight section of a drain line
• (1) At all important (2) changes of direction
• (1) At changes of (2) gradient and levels
• (1) At all important (2) junctions (2 x 2) (4)

5.5
5.5.1 Full-way valve (1)
5.5.2
5.5.A – Non-rising spindle
5.5.B – Valve head
5.5.C – Tapering gate
5.5.D – Seating (4)
5.5.3 Any TWO positions where this type of valve must be installed.

• At the geyser
• At the water meter
• Low- and high-pressure cold water installations
• Low- and high-pressure hot water installations (2 x 1) (2)

5.6 (1) Prevent the siphoning of water out of the cylinder (2) when the cold water is shut off (2)
5.7
5.7.1 Geyser (1)
5.7.2 Heating (1)
5.7.3 Northern side (1)
5.8 (1) After a disruption in the water supply / burst pipe / faulty plumbing
(2) causing gas to be trapped in high points of the hot-water system.
(3) When pressure is applied / taps are opened, the gas blocks the pipes, preventing the flow of water. (3)
[30]

QUESTION 6: ROOFING, STORM WATER, DRAINAGE AND SANITARY APPLIANCES (SPECIFIC)
6.1 25 mm for each 4,8 m (3 mm for each 1 m of 10 mm for each 6 m of 1 : 600) (1)
6.2 Gutter bracket (1)
6.3 (1) Discharged storm water to (2) rivers and dams (2)
6.4 At least 5 m (1)
6.5
6.5.1 Inside of pipes – Be smooth (1)
6.5.2 Joints in pipes – Prevent gases from escaping (1)
6.5.3 Sharp bendings – Must be avoided (1)
6.5.4 Minimum diameter of pipes – 100 mm (1)
6.5.5 Height of vent pipes – At least 1 m (1)
6.6 Waste water – Comes from sink/bath/washbasin/shower
Soil water – Comes from water closet (2)
6.7
6.7.1 Vent valve/Air admittance valve (1)
6.7.2 (1) Valve opens and (2) reduces the vacuum and allows (3) air into the system so that (4) the water can flow away freely / without releasing gases into the building (4)
6.8 Ground water may become polluted (1)
6.9 Any TWO causes of blockages in main sewer pipes:

• Material or objects that should not be flushed
• Tree roots growing into pipe joints
• Soil that seeps through joints
• Heavy traffic over low-lying pipes (2 x 1) (2)

6.10 0,25 kPa (1)
6.11 Any TWO properties of each of the following materials for sanitary fitments:
6.11.1 Ceramic

• Durable
• Pleasant surface
• Glazed surface
• Variety colours
• Strong (2 x 1) (2)

6.11.2 Stainless steel

• Readily available
• Very hygienic (2 x 1) (2)

6.12 Choose a dimension from COLUMN B that matches a term in COLUMN A.
Write only the letter (A-H) next to the question number (6.12.1 – 6.12.5) in the ANSWER BOOK, for example 6.12.6 J.

(5 x 1) (5)
[30]
TOTAL: 200

2.1 Use the information on ANSWER SHEET A and complete the site plan to scale 1 : 200.

3.10 FIGURE 3.10 on ANSWER SHEET B shows a square-based truncated pyramid. Draw on ANSWER SHEET B the pattern development for the pyramid.

5.1 FIGURE 5.1 on ANSWER SHEET C shows layer 1 of a double return angle in a one-brick wall in stretcher bond. Draw in good ratio on ANSWER SHEET C the alternative layer of the brick wall. (6)

5.2 FIGURE 5.2 on ANSWER SHEET D shows the incomplete top view of a concrete manhole. Complete in good ratio the branch connection and pipe work in the manhole. (3)